Answer:
16.25%
=0.163 (correct to 3 decimal places)
Step-by-step explanation:
The child dependency ratio of a population is defined as the number of children (Under 15 years) divided by the working-age population (15–64 years old).
[tex]\mathrm{ Child}\;\mathrm{ dependency}\;\mathrm{ ratio}=\dfrac{{\mathrm{ Population}\,\left( \text{Under 15} \right)}}{{\mathrm{ Population}\,\left( {15-64} \right)}}\times 100[/tex]
From the given table:
Population Under 15 years = 2600
Population of the working class (between 15-64) = 16000
Therefore:
[tex]\mathrm{ Child}\;\mathrm{ dependency}\;\mathrm{ ratio}=\dfrac{2600}{16000}\times 100\\\\=16.25\%[/tex]
=0.163 (correct to 3 decimal places)
The results of a common standardized test used in psychology research is designed so that the population mean is 155 and the standard deviation is 50. A subject earns a score of 155. How many standard deviations from the mean is the value 155
Answer:
The value 155 is zero standard deviations from the [population] mean, because [tex] \\ x = \mu[/tex], and therefore [tex] \\ z = 0[/tex].
Step-by-step explanation:
The key concept we need to manage here is the z-scores (or standardized values), and we can obtain a z-score using the next formula:
[tex] \\ z = \frac{x - \mu}{\sigma}[/tex] [1]
Where
z is the z-score.x is the raw score: an observation from the normally distributed data that we want standardize using [1].[tex] \\ \mu[/tex] is the population mean.[tex] \\ \sigma[/tex] is the population standard deviation.Carefully looking at [1], we can interpret it as the distance from the mean of a raw value in standard deviations units. When the z-score is negative indicates that the raw score, x, is below the population mean, [tex] \\ \mu[/tex]. Conversely, a positive z-score is telling us that x is above the population mean. A z-score is also fundamental when determining probabilities using the standard normal distribution.
For example, think about a z-score = 1. In this case, the raw score is, after being standardized using [1], one standard deviation above from the population mean. A z-score = -1 is also one standard deviation from the mean but below it.
These standardized values have always the same probability in the standard normal distribution, and this is the advantage of using it for calculating probabilities for normally distributed data.
A subject earns a score of 155. How many standard deviations from the mean is the value 155?
From the question, we know that:
x = 155.[tex] \\ \mu = 155[/tex].[tex] \\ \sigma = 50[/tex].Having into account all the previous information, we can say that the raw score, x = 155, is zero standard deviations units from the mean. The subject earned a score that equals the population mean. Then, using [1]:
[tex] \\ z = \frac{x - \mu}{\sigma}[/tex]
[tex] \\ z = \frac{155 - 155}{50}[/tex]
[tex] \\ z = \frac{0}{50}[/tex]
[tex] \\ z = 0[/tex]
As we say before, the z-score "tells us" the distance from the population mean, and in this case this value equals zero:
[tex] \\ x = \mu[/tex]
Therefore
[tex] \\ z = 0[/tex]
So, the value 155 is zero standard deviations from the [population] mean.
What is the quotient if 3/8 of 30 is divided by 15/16 of 5/10?
Answer:
24
Step-by-step explanation:
That would be:
(3/8)(30)
---------------
(15/16)(1/2)
This can be reduced in various ways. First, divide that 30 by 15, obtaining:
6/8
-----------
1/32
Now invert the divisor (1/32) and multiply:
(6/8)(32/1)
This reduces to 6*4, or 24.
a line has a slope of -3/4 and passes through the point (-5, 4). what is the equation of the line?
Answer:
y = -3/4x-1/4
Step-by-step explanation:
The slope intercept form of a line is
y = mx+b
where m is the slope and b is the y intercept
y = -3/4x +b
We have a point (-5,4)
4 = -3/4 (-5) +b
Changing to a common denominator
16/4 = 15/4 +b
subtracting 15/4 from each side
16/4-15/4 = -15/4 +15/4 +b
1/4 = b
y = -3/4x-1/4
Answer:
book
Step-by-step explanation:
kmgktn
Which expression is equivalent to 3(x-6)+5(x-4)
Answer:
[tex]8x-38[/tex]
Step-by-step explanation:
[tex]3(x-6)+5(x-4)\\3x-18+5x-20\\3x+5x-18-20\\8x-38[/tex]
What is the first step of the following division problem? (8x3 – x2 + 6x + 7) ÷ (2x – 1)
Answer:
The first step is to determine how many times 2x goes into 8x^3
Step-by-step explanation:
The first step is to determine how many times 2x goes into 8x^3
4x^2
--------------------------
2x-1 | (8x3 – x2 + 6x + 7
8x^3 -4x^2
Answer:
A
Step-by-step explanation:
i just took the test
A square of area 36cm2 is cut to make two rectangles, A and B The ratio of Area A to Area B is 2 : 1 Work out the dimensions of rectangle A and B
(Need help with this question)
Answer:
Given..hope it helps
Step-by-step explanation:
Area of square= 36cm2 = total area
Side of square= √36= 6cm
Ratio a:b = 2:1
so let's take total area as 3x
while a is 2x and b is 1x
3x= 36 (given)
x= 36/3 = 12
so area of each rectangle--
area A= 2x= 24cm2
area B= x= 12cm2
While finding the dimensions, they both have a common length since they are from the same square which will be 6cm (side)
So,
Dimensions of rectangle A= 6cm * 4cm
Dimensions of rectangle B= 6cm * 2cm
Urban Community College is planning to offer courses in Finite Math, Applied Calculus, and Computer Methods. Each section of Finite Math has 40 students and earns the college $40,000 in revenue. Each section of Applied Calculus has 40 students and earns the college $60,000, while each section of Computer Methods has 10 students and earns the college $26,000. Assuming the college wishes to offer a total of seven sections, accommodate 220 students, and bring in $292,000 in revenues, how many sections of each course should it offer?
Finite Math section(s)
Applied Calculus section(s)
Computer Methods section(s)
Answer:
meh
Step-by-step explanation:
A Biology test contains 10 multiple choice questions each with 5 choices and one correct answer. If a law school student just randomly guesses on each of the 10 questions, i.e., the probability of getting a correct answer on any given question is 0.2. Assume that all questions are answered independently. (a) What is the probability that the student answers at least 9 questions correctly
Answer:
0.0004% probability that the student answers at least 9 questions correctly
Step-by-step explanation:
For each question, there are only two possible outcomes. Either the student guesses the correct answer, or he does not. All questions are answered independently. This means that we use the binomial distribution to solve this question.
Binomial probability distribution
The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
In which [tex]C_{n,x}[/tex] is the number of different combinations of x objects from a set of n elements, given by the following formula.
[tex]C_{n,x} = \frac{n!}{x!(n-x)!}[/tex]
And p is the probability of X happening.
In this question, we have that:
[tex]n = 10, p = 0.2[/tex]
What is the probability that the student answers at least 9 questions correctly
[tex]P(X \geq 9) = P(X = 9) + P(X = 10)[/tex]
In which
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
[tex]P(X = 9) = C_{10,9}.(0.2)^{9}.(0.8)^{1} = 0.000004[/tex]
[tex]P(X = 10) = C_{10,10}.(0.2)^{10}.(0.8)^{0} \approx 0 [/tex]
[tex]P(X \geq 9) = P(X = 9) + P(X = 10) = 0.000004 + 0 = 0.000004[/tex]
0.0004% probability that the student answers at least 9 questions correctly
Which is enough information to prove that line s is parallel to line t
Answer:
line s and t would not meet even if you extend them and also they have the same slope and gradient
Section 1: Write the following times in 24-hour clock time:
a) 7:15 a.m -
b) 1:05 am
c) 2:01 p.m
d) 9:22 p.m
e) 12:25 am
Section 2: Write the following times in 12-hour clock time.
a) 1155 hours
b) 1005 hours
c) 1714 hours
d) 0756 hours
e) 1345 hours
Answer:
Section 1:
a) 7:15 a.m - 19:15
b) 1:05 am - 01:05
c) 2:01 p.m - 14:01
d) 9:22 p.m - 21:22
e) 12:25 am- 24:25
Section 2:
a) 1155 hours - 11:55am
b) 1005 hours -10:05am
c) 1714 hours - 5:14pm
d) 0756 hours - 7:56am
e) 1345 hours- 1:45pm
Answer:
12:25 am= 00:25
Step-by-step explanation:
2.24 Exit poll: Edison Research gathered exit poll results from several sources for the Wisconsin recall election of Scott Walker. They found that 57% of the respondents voted in favor of Scott Walker. Additionally, they estimated that of those who did vote in favor for Scott Walker, 33% had a college degree, while 45% of those who voted against Scott Walker had a college degree. Suppose we randomly sampled a person who participated in the exit poll and found that he had a college degree. What is the probability that he voted in favor of Scott Walker? (please round to 4 decimal places)
Answer:
0.4929 = 49.29% probability that he voted in favor of Scott Walker
Step-by-step explanation:
Bayes Theorem:
Two events, A and B.
[tex]P(B|A) = \frac{P(B)*P(A|B)}{P(A)}[/tex]
In which P(B|A) is the probability of B happening when A has happened and P(A|B) is the probability of A happening when B has happened.
In this question:
Event A: Having a college degree.
Event B: Voting for Scott Walker.
They found that 57% of the respondents voted in favor of Scott Walker.
This means that [tex]P(B) = 0.57[/tex]
Additionally, they estimated that of those who did vote in favor for Scott Walker, 33% had a college degree
This means that [tex]P(A|B) = 0.33[/tex]
Probability of having a college degree.
33% of those who voted for Scott Walker(57%).
45% of those who voted against Scott Walker(100 - 57 = 43%). So
[tex]P(A) = 0.33*0.57 + 0.45*0.43 = 0.3816[/tex]
What is the probability that he voted in favor of Scott Walker?
[tex]P(B|A) = \frac{0.57*0.33}{0.3816} = 0.4929[/tex]
0.4929 = 49.29% probability that he voted in favor of Scott Walker
Oliver had $43 on the day before his birthday. After he received some money for his birthday, he had $68. Write an equation to find how much money Oliver received for his birthday.
Answer:
$25
Step-by-step explanation
If oliver had $43 before his birthday he was given (+) an amount of money, in order to find out how much money was given you need to reverse the equation (-) $68-$43= $25
An analysis of 8 used trucks listed for sale in the 48076 zip code finds that the power model ln(\hat{price})=3.748-0.1395ln(miles)ln(price^)=3.748−0.1395ln(miles), for price (in thousands of dollars) and miles driven (in thousands), is an appropriate model of the relationship. If a used truck has been driven for 47,000 miles, which of the following is closest to the predicted price for the truck?(A) $9.46(B) $24.80(C) $3,210.00(D) $9,460.00(E) $24,800.00
Answer:
(E) $24,800.00
Step-by-step explanation:
[tex]ln(\hat{price})=3.748-0.1395ln(miles)[/tex]
If a used truck has been driven for 47,000 miles
Miles=47 (in thousands)
We therefore have:
[tex]ln(\hat{price})=3.748-0.1395ln(47)\\ln(\hat{price})=3.2109\\$Take the exponential of both sides\\e^{ln(\hat{price})}=e^{3.2109}\\Price=e^{3.2109}\\$Price=24.80 \\Since the price is in thousands of dollars\\Price=24.80 X \$1000\\Predicted Price=\$24800.00[/tex]
The correct option is E.
In a group, 10 freshmen have mean GPA of 3.5; 20 sophomores have a mean GPA of 2.9; 25 juniors have a mean GPA of 3.2; and 15 seniors have a mean GPA of 3.4. What is the mean of the entire group
Answer:
[tex] T_1 = 10*3.5 = 35[/tex]
[tex] T_2 = 20*2.9 = 58[/tex]
[tex] T_3 = 25*3.2 = 80[/tex]
[tex] T_4 = 15*3.4 = 51[/tex]
[tex] \bar X= \frac{T_1 +T_2 +T_3 +T_4}{10+20+25+15}= \frac{35+58+80+51}{10+20+25+15} = 3.2[/tex]
Step-by-step explanation:
For this case we have the following info given:
[tex] n_1= 10 , \bar X_1 = 3.5[/tex] for freshmen
[tex] n_2= 20 , \bar X_2 = 2.9[/tex] for sophomores
[tex] n_3= 25 , \bar X_3 = 3.2[/tex] for juniors
[tex] n_4= 15 , \bar X_4 = 3.4[/tex] for seniors
For this case we can use the formula for the sample mean in order to find the total of each group:
[tex] \bar X =\frac{\sum_{i=1}^n X_i}{n}[/tex]
[tex]T= \sum_{i=1}^n X_i = n *\bar X[/tex]
And replacing we got:
[tex] T_1 = 10*3.5 = 35[/tex]
[tex] T_2 = 20*2.9 = 58[/tex]
[tex] T_3 = 25*3.2 = 80[/tex]
[tex] T_4 = 15*3.4 = 51[/tex]
And the grand mean would be given by:
[tex] \bar X= \frac{T_1 +T_2 +T_3 +T_4}{10+20+25+15}= \frac{35+58+80+51}{10+20+25+15} = 3.2[/tex]
A fuel oil tank is an upright cylinder, buried so that its circular top is 8 feet beneath ground level. The tank has a radius of 6 feet and is 18 feet high, although the current oil level is only 12 feet deep. Calculate the work required to pump all of the oil to the surface. Oil weighs 50\, \hbox{lb/ft}^3.
Answer:
1.504×10⁶ ft·lb
Step-by-step explanation:
We understand the top of the oil in the tank is 12 ft below ground level, and the bottom of the tank is 8+18=26 ft below ground level. Then the average depth of the oil is (12+26)/2 = 19 ft below ground level.
The height of the oil in the tank is 26-12=14 ft, so the volume of it is ...
V = πr²h = π(6 ft)²(14 ft) = 504π ft³ ≈ 1583.36 ft³
__
So, the work required to raise that volume of oil to the surface is ...
(1538.36 ft³)(50 lb/ft³)(19 ft) = 1.504×10⁶ ft·lb
what is the midpoint of the segment shown below?
(1, 2) (1,-5)
A. (1, -3/2)
B. (2, -3/2)
C. (2, -3)
D. (1, -3)
Answer:
The answer is A (1,-3/2)
Step-by-step explanation:
Add both x coordinates, divide by 2
Add both y coordinates, divide by 2
A fair 6-sided die is colored in the following way: The faces of 1 - 3 are colored red. The faces of 4 and 5 are colored blue. The face of 6 is colored green. What is the probability that the face comes up red OR a prime number
Answer:
There are 6 total possibilities, 3 red faces and 3 prime numbers however, 2 and 3 are prime numbers and they are red as well so total successful outcomes = 3 + 3 - 2 = 4. This means that the answer is 4 / 6 or 2 / 3.
Answer:
[tex]\frac{2}{3}[/tex]
Step-by-step explanation:
[tex]1 \: 2\:3[/tex] are red
[tex]5[/tex] is prime.
Total of [tex]4[/tex] possibilities out of [tex]6[/tex]
[tex]\frac{4}{6}[/tex]
Which expression is equivalent to the given expression? (3m-4)^3(3m^5)
Answer: D.
Step-by-step explanation:
You want to cube each term in the parentheses. When you take an exponent to an exponent, you just multiply them. You get (27m^-12). In order to get rid of that negative exponent, you should put a one over the m term and make -12, +12:
[tex](\frac{27}{m^12} )(3m^5)[/tex]
Multiply the numerators to get:
[tex]81m^5[/tex]
You now have:
[tex]\frac{81m^5}{m^12}[/tex]
When you divide exponents, you subtract them. 5 - 12 = -7
You have m^-7 which is the same as 1/m^7. Finally, mulitply that by the 81 we left out to get the answer of D.
The expression equivalent to the given expression (3m⁻⁴)³(3m⁵) is 81/m⁷. So, option D is correct.
What is exponentiation?Exponentiation is a mathematical operation that involves two numbers, the base b, and the exponent or power n, and is pronounced as "b raised to the power of n." It is written as bⁿ and is pronounced as "b raised to the power of n."
When n is a positive integer, bⁿ = b × b × b ×...× b
and b⁻ⁿ = 1/bⁿ
If n = 0, then b⁰ = 1.
How to solve this problem?Here, (3m⁻⁴)³(3m⁵) = (3³)(m⁻⁴)³(3m⁵) = (27m⁻¹²)(3m⁵) = 81m⁵⁻¹² = 81/m⁷
Therefore, the expression equivalent to the given expression (3m⁻⁴)³(3m⁵) is 81/m⁷. So, option D is correct.
Learn more about exponentiation here -
https://brainly.com/question/14513824
#SPJ2
A woman forgot her bank ATM PIN but she was able to recall some of the pin.
1)the 1st digit is half of the 2nd pin
2)the sum of 2nd and 3rd is equal to 10
3)the 4th is equal to the 2nd plus 1
4)the sum of all digits is 23
show workings please
what is the ATM digit?
The PIN is 4829
Step-by-step explanation:
let s take 4 numbers a b c and d
the PIN is abcd
we know that
(1) a = b/2
(2) b+c=10
(3) d=b+1
(4) a+b+c+d=23
from (2) c = 10 - b
from (3) d = b + 1
so (4) gives
b/2 + b + 10 - b + b +1 = 23
so
3/2 b = 23 -11 = 12
b = 12*2/3 = 8
so d = 9
c = 10-8=2
and a = 4
so the PIN is 4829
thank you
Kortholts that fail to meet certain precise specifications must be reworked on the next day until they are within the desired specifications. A sample of one day's output of kortholts from the Melodic Kortholt Company showed the following frequencies: Plant A Plant B Row Total Specification Met 85 35 120 Specification Not Met 15 25 40 Column Total 100 60 160 Find the chi-square test statistic for a hypothesis of independence. Multiple Choice 7.22 14.22 -0.18 14.70
Answer:
The value of Chi-square test statistic for a hypothesis test of independence is 14.22.
Step-by-step explanation:
The data provided is for one day's output of Kortholt's from the Melodic Kortholt Company.
The formula to compute the chi-square test statistic for a hypothesis of independence is:
[tex]\chi^{2}=\sum {\frac{(O-E)^{2}}{E}}[/tex]
The formula to compute the expected frequencies (E) is:
[tex]E=\frac{\text{Row Total}\times \text{Column Total}}{N}[/tex]
Consider the Excel output attached.
Compute the value of Chi-square test statistic as follows:
[tex]\chi^{2}=\sum {\frac{(O-E)^{2}}{E}}[/tex]
[tex]=1.333+2.222+4.000+6.667\\=14.222\\\approx 14.22[/tex]
Thus, the value of Chi-square test statistic for a hypothesis test of independence is 14.22.
85 points!! | All of the following expressions have the same value, when x= -2 and y= 4, except
-2xy
0-4x2
0x²y
0 (-2) ²y
Answer:
They have two sets of equal answers...
Step-by-step explanation:
-2 * 2 * 4 = -16
0 - 4 * -2 * -2 = -16
0 * -2 * -2 * 4 = 0
0 * 4 * 4 = 0
Suppose a simple random sample of size 50 is selected from a population with σ=10σ=10. Find the value of the standard error of the mean in each of the following cases (use the finite population correction factor if appropriate).
a. The population size is infinite.
b. The population size is N=50,000.N=50,000.
c. The population size is N=5000.N=5000.
d. The population size is N=500.N=500.
Answer:
a) [tex]\sigma_{\bar x} = 1.414[/tex]
b) [tex]\sigma_{\bar x} = 1.414[/tex]
c) [tex]\sigma_{\bar x} = 1.414[/tex]
d) [tex]\sigma _{\bar x} = 1.343[/tex]
Step-by-step explanation:
Given that:
The random sample is of size 50 i.e the population standard deviation =10
Size of the sample n = 50
a) The population size is infinite;
The standard error is determined as:
[tex]\sigma_{\bar x} = \dfrac{\sigma}{\sqrt{n}}[/tex]
[tex]\sigma_{\bar x} = \dfrac{10}{\sqrt{50}}[/tex]
[tex]\sigma_{\bar x} = 1.414[/tex]
b) When the population size N= 50000
n/N = 50/50000 = 0.001 < 0.05
Thus ; the finite population of the standard error is not applicable in this scenario;
Therefore;
The standard error is determined as:
[tex]\sigma_{\bar x} = \dfrac{\sigma}{\sqrt{n}}[/tex]
[tex]\sigma_{\bar x} = \dfrac{10}{\sqrt{50}}[/tex]
[tex]\sigma_{\bar x} = 1.414[/tex]
c) When the population size N= 5000
n/N = 50/5000 = 0.01 < 0.05
Thus ; the finite population of the standard error is not applicable in this scenario;
Therefore;
The standard error is determined as:
[tex]\sigma_{\bar x} = \dfrac{\sigma}{\sqrt{n}}[/tex]
[tex]\sigma_{\bar x} = \dfrac{10}{\sqrt{50}}[/tex]
[tex]\sigma_{\bar x} = 1.414[/tex]
d) When the population size N= 500
n/N = 50/500 = 0.1 > 0.05
So; the finite population of the standard error is applicable in this scenario;
Therefore;
The standard error is determined as:
[tex]\sigma _{\bar x} = \sqrt{\dfrac{N-n}{N-1} }\dfrac{\sigma}{\sqrt{n} } }[/tex]
[tex]\sigma _{\bar x} = \sqrt{\dfrac{500-50}{500-1} }\dfrac{10}{\sqrt{50} } }[/tex]
[tex]\sigma _{\bar x} = 1.343[/tex]
What value of x makes 3(x + 4) = 3x + 4 true?
Well lets see.
[tex]3(x+4)=3x+4\implies 12 = 4\implies x\notin\mathbb{C}[/tex].
There are no such x-es that satisfy the equation.
An organization will give a prize to a local artist will be randomly chosen from among 6 painters,2 sculptors, and 9 photographers. What is the probability that the artist chosen will be a painter or a sculptor?
Answer: [tex]\bold{\dfrac{8}{17}=47.1\%}[/tex]
Step-by-step explanation:
[tex]\dfrac{\text{painter or sculptor}}{\text{total artists}}=\dfrac{6+2}{6+2+9}=\dfrac{8}{17}[/tex]
In the first year if ownership, a new car lose 20% of its value. If a car lost $4,200 value in the first year, how much did the car originally cost?
Answer:
21,000$
Step-by-step explanation:
part to whole method
20/100 and 4,200/
How many 20s to get to 4,200?
Determine the next term in the sequence.
14,33,55,83,114....
Answer:
You can't find the next solution without more information.
Step-by-step explanation:
The volume of the box shown in the diagram is 40π3 cubic units. Find the length of ‘x’.
Answer:
4: 4[tex]\pi^2[/tex]
Step-by-step explanation:
2[tex]\pi[/tex] x 5 x [tex]x[/tex] = 10[tex]\pi x[/tex]
10[tex]\pi x[/tex] = 40[tex]\pi ^3}[/tex]
x = 4[tex]\pi^2[/tex]
Answer:
4π units
Step-by-step explanation:
v=lwh
40π^3=2π×5×h
40π^3=10π^2×h
h=40π^3/10π^2
h=4π units
mark brianliest if my answer suit your question please.
At the beginning of the season,jamie pays full price for a ticket to see the panthers,her favorite baseball team.
Corrected Question
At the beginning of the season, Jamie pays full price($49.64) for a ticket to see the panthers, her favorite baseball team. Ticket prices decrease $0.41 for every game the panthers lose this season. the panthers currently have 33 wins and 31 losses.
(a)Represent the total change in the cost of a ticket given their losses.
(b) What is the cost of a ticket for the next game they play?
Answer:
(a)$(49.64-0.41x)
(b)$36.93
Step-by-step explanation:
(a)Cost of a Full Ticket =$49.64
Let x be the number of losses
The ticket price reduces by $0.41 for every loss
Therefore:
Ticket Price after x losses =$(49.64-0.41x)
Therefore, total change in the cost of a ticket given their losses=$(49.64-0.41x)
(b)For this season the Panthers has suffered 31 losses.
Number of Losses, x=31
Therefore, cost of a ticket for the next game they play
= $(49.64-0.41*31)
=49.64-12.71
=$36.93
four apples and one banana cost £1.40 seven apples and one banana cost £2.00 work out the cost of an apple and the cost of a banana .
Answer:
apple: £0.20banana: £0.60Step-by-step explanation:
Let "a" and "b" represent the costs of one apple and one banana, respectively. Then the purchases can be written ...
4a +b = 1.40
7a +b = 2.00
Subtracting the first equation from the second gives ...
(7a +b) -(4a +b) = (2.00) -(1.40)
3a = 0.60 . . . . simplify
a = 0.20 . . . . . .divide by 3
Using this in the first equation, we have ...
4(0.20) +b = 1.40
b = 0.60 . . . . . subtract 0.80
The cost of an apple is £0.20; the cost of a banana is £0.60.
which law would you use to simply the expression 3^10/3^4 quotient power power of a quotient product of powers power of a product