A SCHOOL HAS 320 GIRLS AND 250 BOYS

THE PROBABILITY THAT A GIRL IS LEFT-HANDED IS 0.2
THE PROBABILITY THAT A BOY IS LEFT-HANDED IS 0.1

ESTIMATE THE NUMBER OF LEFT-HANDED STUDENTS IN THE SCHOOL

Answer:

The answer is option 1 and 3.

Step-by-step explanation:

Firstly, you have to find the simplest form of the ratio by dividing the common numbers :

[tex]10:16 = \frac{10}{16} = \frac{5 \times 2}{8} = \frac{5}{8} [/tex]

Given that the simplest ratio is 5:8. Next, you have to simplify all the options given and which is equivalent to 5:8 :

Option 1,

[tex]30 \: to \: 48 = 30:48 = \frac{30}{48} = \frac{5 \times 6}{8 \times 6} = \frac{5}{8} = 5:8 \: (correct)[/tex]

Option 2,

[tex]25:35 = \frac{25}{35} = \frac{5 \times 5}{7 \times 5} = \frac{5}{7} = 5:7 \: (incorrect)[/tex]

Option 3,

[tex] \frac{40}{64} = \frac{5 \times 8}{8 \times 8} = \frac{5}{8} = 5:8 \: (correct)[/tex]

Option 4,

[tex]8:32 = \frac{8}{32} = \frac{1 \times 8}{4 \times 8} = \frac{1}{4} = 1:4\: (incorrect)[/tex]

Option 5,

[tex]5 \: to \: 15 = \frac{5}{15} = \frac{1 \times 5}{3 \times 5} = \frac{1}{3} = 1:3 \: (incorrect)[/tex]

Answer:

r = 6

Step-by-step explanation:

Calculate the slope m using the slope formula and equate to [tex]\frac{3}{2}[/tex]

m = [tex]\frac{y_{2}-y_{1} }{x_{2}-x_{1} }[/tex]

with (x₁, y₁ ) = ( 3, - 6) and (x₂, y₂ ) = (11, r)

m = [tex]\frac{r+6}{11-3}[/tex] = [tex]\frac{r+6}{8}[/tex] = [tex]\frac{3}{2}[/tex] ( cross- multiply )

2(r + 6) = 24 ( divide both sides by 2 )

r + 6 = 12 ( subtract 6 from both sides )

r = 6

Answer:

t= -105

Step-by-step explanation:

To solve the equation, we want to find out what t is. In order to do this, we have to get t by itself. Perform the opposite of what is being done to the equation. Keep in mind, everything done to one side, has to be done to the other.

-1/15t=7

t is being multiplied by -1/15. The opposite of multiplication is division. Divide both sides by -1/15.

-1/15t/-1/15=7/ -1/15

t=7/ -1/15

Instead of dividing a number by a fraction, you can multiply the number by the reciprocal of the fraction.

To find the reciprocal, flip the numerator (top number) and denominator (bottom number).

-1/15--flip--> -15/1=-15

Substitute -15 in for -1/15, and switch the division sign to a multiplication sign.

t= 7* -15

t=-105

Let's check out solution. Plug -105 back in for t in the original equation.

-1/15t=7

-1/15*-105=7

7=7

Both sides are the same, so we know that t=-105.

Answer:

t=-105

Step-by-step explanation:

[tex]-\frac{1}{15} t =7[/tex]

What we need to do here is to isolate t.

Let's multiply both sides by -15.

[tex]-\frac{1}{15}t * -15 = 1t[/tex]

7*-15= -105

t=-105

Answer:

A. is the correct answer

Step-by-step explanation:

the answer is 27

Answer:

A. 25

Step-by-step explanation:

f(x)= 8x - 7

f(4)= 8*4 - 7= 25

f(4)= 25

Answer:

the answer is D

Step-by-step explanation:

Answer: 40

Step-by-step explanation:

Answer:

40 basketballs in 5 hours

Step-by-step explanation:

If in 1/2 hour she makes 4, multiply it by 2 to know how much she can make in a wholw hour. So she can make 8

Multiply how much she can make every hour by the amount of hours.

8 x 5 = 40

Answer:

256

Step-by-step explanation:

To calculate the mean, we simply divide the sum of the values by the count.

For the first set, the mean is as follows;

(9 + 5 + 2 + y + x)/5 = (x + y + 16)/5

For the second set;

(8 + x + 4 + 1 + 3)/5 = (16 + x)/5

Since both are divided by 5, we can eliminate it

Mean of first set is twice the second

This means that;

x + y + 16 = 2(16 + x)

x + y + 16 = 32 + 2x

y = 32-16+2x-x

y = 16 + x

Now we want to calculate

(y-x)^2

substitute the value of y here

(16+x-x)^2

= 16^2 = 256

Answer:

Chris' initial investment is $5000. The interest rate is 2% quarterly for 4 years.

Step-by-step explanation:

Answer:

1). Number of kids on the other side = 16

2). Brian took the time to each piece of pie = 20 seconds

Step-by-step explanation:

1). Let the number of kids on one side = x

  Then the number of kids on other side = 2x

  3 adults helped the side having number of kids = x, then the number of people on this side = x + 3

Since the total number of people on this side = 11

Then the equation will be,

x + 3 = 11

x = 11 - 3

x = 8

Then number of kids on the other side = 2x = 2×8

                                                                           = 16

2). By unitary method,

∵ Brian took the time to eat 6 pieces of the pie = 2 minutes

∴ Brian will take time to eat 1 piece of pie = [tex]\frac{2}{6}[/tex] minutes

                                                                     = [tex]\frac{2}{6}\times 60[/tex] seconds

                                                                     = 20 seconds

Answer:

5

Step-by-step explanation:

Add 6 to both sides. The answer is 5.

Answer:

5

Step-by-step explanation

since we are looking for the value of x,we have to make it the subject of the formula(stand alone).

Therefore,-6 would cross over the equality sign and it would become =6.

NOTE:when a negative number crosses the equality sign,it becomes a positive number.

This implies that x= -1+6

NOTE:when you come across - + +(minus plus plus),u would have to minus.

and to know the sign that would be at the front of the answer,just take a look at the sign the bigger number holds.At this point it is plus.

Therefore,x= -1 +6

x=5(u could have stated it was +5 but it isnt necessary since there is an invisible plus sign at the front of a number as long as minus is not there

Answer:

3

Step-by-step explanation:

SSS similarity states that all 3 sides must be proportional for the triangles to be similar

Answer:

y= -7/-4/-1/2/5/8

Step-by-step explanation:

Answer:

-7, -1, 8

Step-by-step explanation:

substitute the numbers in the equation given:

1) y=3x-1

y=3(-2) -1

y=-6 -1

y=-7

2)y=3x-1

y=3(0) -1

y=0-1

y=-1

3) y=3x-1

y=3(3) -1

y=9-1

y=8

Answer:

The expression as a sum of terms is [tex]2\cdot a^{\frac{3}{2} } - 4\cdot a^{-\frac{1}{2} }[/tex].

Step-by-step explanation:

The expression to be rewritten has the following form:

[tex]\sqrt{a} \cdot (2\cdot a^{2}-\frac{4}{a} )[/tex]

A polynomial as a sum of terms consists in a sum of terms of the form [tex]c_{i} \cdot a^{k(i)}[/tex], where [tex]c_{i}[/tex] and [tex]k_{i}[/tex] are the i-th coefficient and exponent. The expression has to be expanded to create the sum of terms:

[tex]a^{\frac{1}{2} }\cdot (2\cdot a^{2} - 4\cdot a^{-1})[/tex]

[tex]2\cdot a^{1 + \frac{1}{2} } - 4\cdot a^{-1+\frac{1}{2} }[/tex]

[tex]2\cdot a^{\frac{3}{2} } - 4\cdot a^{-\frac{1}{2} }[/tex]

The expression as a sum of terms is [tex]2\cdot a^{\frac{3}{2} } - 4\cdot a^{-\frac{1}{2} }[/tex].

Answer:

D is answer. So if we do -2 * 3 we get -6, -6-4 = -10. Well that doesn't work for a because its 10 not -10. But we have spotted something already. We do have -2 and -10. Those two work we just tested it, but A doesn't work. The only pair that has the -2 and -10 is d. Sorry for bad english, its not native language

Answer:

d

Step-by-step explanation:

Answer:

tuv x is 6

uvw x is 0

Step-by-step explanation:

Answer:

6x^2 -4x +8

Step-by-step explanation:

(6x^2+ 5) - (4x - 3)

Distribute the minus sign

(6x^2+ 5) - 4x + 3

Combine like terms

6x^2 -4x +8

Answer:

Step-by-step explanation:

C

Answer:

x= -1/2 and x=2/11

Step-by-step explanation:

Write the 7x as a difference. It'll make it easier to factor out. An example of this would be 11x-4x

Therefore, the equation would look like this: 22x^2 + 11x-4x -2 =0

Look at it as if there are two equations: 22x^2+11x and -4x-2

Factor out the greatest common factor, which is 11 from the first equation. The equation will then look like this: 11x(2x+1)

Take the GCF for the second equation as well (which is -2). The equation should then also look like this: (2x+1)

Use the numbers on the outside of each of the parenthesis to form its own equation (to factor it out). This will be 11x-2

Now we have factored! Since the parenthesis equations are the same, we know that that is also part of the equation, so:

(11x-2)(2x+1)

Solve each equation for x by equaling them both to zero

Answer:

C. 14.75

Step-by-step explanation:

To find mean is fairly easy. All you have to do is add all of the numbers in your data set, and then divide it by the total amount of numbers in the set. So:

12 + 17 + 16 + 10 + 20 + 13 + 14 +14 + 12 + 12 + 19 + 18

Total numbers in the set: 12

All numbers added together: 177

177 / 12 = 14.75

brainliest is always epic :)

Answer:

Step-by-step explanation:

1. First add all the listed numbers which equals to 177

2. Divide 177 by the amount of number given above so there are

12 numbers

So 177÷12= 14.75

Answer is c

Answer:

Probability is 2/5 or 40%.

Step-by-step explanation:

4/(4+2) = 4/6 = 2/3 first black pen is chosen.

3/5 - second pen is chosen without replacement.

2/3 *3/5= 2/5 - the probability a black pen was chosen, and then another black pen without replacement.

2/5*100 % = 40 %

Answer:

To solve this problem, we need to write each number in two different ways, we could use percetanges or fractions.

This number can be written in scientific notation like [tex]4 \times 10^{7}[/tex], where the exponent depends on the amount of zeros the quantity has.

A second way to write this number would be as a product [tex]2 \times 20,000,000.00[/tex].

Similarly, this number can be written in scientific notation [tex]2 \times 10^{-2}[/tex], also, we can write it as a fraction [tex]\frac{2}{100}[/tex].

This number in scientific notation would be [tex]1.05 \times 10^{8}[/tex]. As a product would be

[tex]1050 \times 100000[/tex].

In scientific notation would be [tex]7 \times 10^{-9}[/tex]. As a fraction would be [tex]\frac{7}{1000000000}[/tex].

In scientific notation would be [tex]4.56983 \times 10^{5}[/tex]. Also, we can write it as a sum

[tex]450,000 + 6,983[/tex]

In scientific notation would be [tex]6.73 \times 10^{-7}[/tex]. As a fraction would be [tex]\frac{673}{1000000000}[/tex]

Answer:

The overview of the given situation is described in the explanation segment below.

Step-by-step explanation:

As we know that the determination's coefficient will be:

⇒  [tex]R^2[/tex]

(Percent of variance in the answer variable described by the explanatory variable).

Now the correlation among the two variables will be:

As we know,

⇒  [tex]r^2=R^2[/tex]

⇒  [tex]r^2=0.79[/tex]

⇒  [tex]r=\sqrt{0.79}[/tex]

⇒  [tex]r=0.889[/tex]

The percentage value of 79% given in the context is the percentage of variation in the prevalence of Hantavirus which can be explained by precipitation. Hence, the coefficient of determination, R².

Hence, the metric shows that 79% of changes in prevalence is caused by the regression line, hence the R² value.

Learn more :https://brainly.com/question/18405415

Answer:

AB = 42.15 units

Step-by-step explanation:

In triangle ABD,

By applying Cosine rule in this triangle,

cos(30)°= [tex]\frac{\text{Adjacent side}}{\text{Hypotenuse}}[/tex]

[tex]\frac{\sqrt{3} }{2}[/tex] = [tex]\frac{AD}{AB}[/tex]

[tex]\frac{\sqrt{3}}{2}=\frac{AD}{47}[/tex]

AD = [tex]\frac{47\sqrt{3}}{2}[/tex]

By applying tangent rule in ΔACD,

tan(44)° = [tex]\frac{\text{Opposite side}}{\text{Adjacent side}}[/tex]

tan(44)° = [tex]\frac{AD}{x}[/tex]

0.9657 =  [tex]\frac{\frac{47\sqrt{3}}{2}}{x}[/tex]

0.9657 = [tex]\frac{47\sqrt{3}}{2x}[/tex]

x = [tex]\frac{47\sqrt{3}}{2(0.9657)}[/tex]

x = 42.15

  ≈ 42.2 units

Answer:

  B' = (5, -4)

Step-by-step explanation:

The picture is illegible, but we think B is (1, 4).

After rotation 180°, both coordinates are negated, so the point is ...

  B" = -(1, 4) = (-1, -4)

After reflection across x=2, the x-coordinate is subtracted from 2·2 = 4:

  B' = (4 -(-1), -4)

  B' = (5, -4)

Answer:

a line with points A and B is True

Answer:

4 adults : 3 children

Step-by-step explanation:

Answer:

Exactly 26 cookies fit and there would be 0.75 of cookie space left over.

Step-by-step explanation:

In this case, we must calculate the area of a cookie and the total area of the cookie tray,

give us the diameter of the cookie, we need the radius, we know that the radius is half the diameter, so:

r = d / 2 = 1/2

the area would be:

A = pi * r ^ 2

replacing:

A = 3.14 * (1/2) ^ 2

A = 0.785

The area for each cookie is 0.785 in ^ 2

Now the area of the cookie tray would be:

A = 7 * 3

A = 21 in ^ 2

Therefore a total of:

 21 / 0.785 = 26.75

Which means that exactly 26 cookies fit and there would be 0.75 of cookie space left over.

Answer:

PV/nR = T

Step-by-step explanation:

PV = nRT

Divide each side by nR

PV/nR = nRT/ nR

PV/nR = T

Answer:

So we know that P*V = n*R*T im guessing

So that means that we divide it by how much we are multiplying by T aka n*R

so PV/nR = T

I am guessing that this is no physics fomula or math formula with things I dont know but if these are just random vars this is the answer.

Step-by-step explanation:

Answer: B

Step-by-step explanation:

 In the systems of equation it already gives you the solution for x  which is -2 so all you have to do is substitute -2 into the first equation and solve for y.

y= 2/3x + 3    

x= -2

Substitute x for -2

y = [tex]\frac{2}{3}* \frac{-2}1} + 3[/tex]  

y= [tex]\frac{-4}{3}[/tex] + [tex]\frac{3}{1}[/tex]    

y = [tex]\frac{5}{3}[/tex]  

so now you have the solution like this [tex](-2,\frac{5}{3})[/tex]

Let's start with part a, finding the maximum and minimum.

Answer a: Max temp is -5 C on day 200.  Min temp is -79 C on day 500.

Sine model.

We're looking for a model

T(n) = A sin( ωn - p ) + o

where T(n) is the estimated temperature on day n, A the amplitude of the variation, omega the radial frequency of variation, p a phase shift and o an offset, the average temperature.

Averaging min and max gives -42 C; that's the offset, what we get when the sine is zero.  o = -42 C.

That's pretty close to the value on day 0 so we'll just use a sine function without any phase shift, p = 0.

Subtracting min from max gives a total span of 74 C degrees, so a sinusoidal amplitude that's half that, A = 37 C.

From max to min is a half period, or about a half period since we're only seeing every 100 days.  That's 300 days, so a full cycle about every 600 days.

We want the argument to sine to go from 0 to 2pi as we complete a single period, 600 days,  So when n=600 this term must be 2π, so it's of the form

ωn = 2 π n / 600.

Putting it all together we get our model:

Answer b: T(n) = 37 sin(2 π n / 600) - 42

We already estimated the period at 600 days.  That's a full year.

Answer c: 600 days

We can see a full period is closer to 700 days (compare day 500 and day 1200, and also day 600 and day 1300) and the phase shift might need adjusting, but I think we pretty much did as they asked so I'll stop here.