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3 years ago

The 20 girls in the class represented 55% of the students in the class. How many students are in the class?

Mathematics

1 answer:

inna [77]3 years ago

4 0

Answer:

There are 31 students in the class.

Step-by-step explanation:

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(WILL MARK AS BRAINLEIST)

Bogdan [553]

Answer:

Step-by-step explanation:

20%

8 0

3 years ago

Read 2 more answers

What is the coefficient of 3x+-12

melisa1 [442]

Answer:

The coefficient of $3x + 12$ is 3.

Step-by-step explanation:

The coefficient of an equation is the number that is multiplied by the varible. In this equation, $x$ is being multiplied by 3, so the coefficient is 3.

4 0

2 years ago

If 20 divided by 5 = 4 <br> Then 20 divided by 5.5=4.?

ahrayia [7]

Answer:

Step-by-step explanation:

20 divided by 5.5 is a decimal 3.63

3 0

3 years ago

Plz help!

jek_recluse [69]

Step-by-step explanation:

let's look at the last line :

x³ + 8x - 3 = Ax³ +5Ax + Bx² + 5B + Cx + D

since we find A, B, C, and D by simply comparing the factors of the various terms in x (or constants) in both sides of the equation, we need to combine a few terms on the right hand side (so that we have one term per x exponent grade).

x³ + 8x - 3 = Ax³ + (5A + C)x + Bx² + (5B + D)

by comparing now both sides, to make both sides truly equal, the factors have to be equal.

A = 1 (the same as for x³ on the left hand side).

B = 0 (a we have no x² on the left side).

5A + C = 8 (a 8 is the factor of x in the left side).

5×1 + C = 8

5 + C = 8

C = 3

5B + D = -3 (as the constant term is -3 on the left side).

5×0 + D = -3

D = -3

so, the 4th answer option is correct.

7 0

2 years ago

A 140 kg camera is suspended by two wires over a 40 metre wide football field to get shots of the action from above. At one poin

Katen [24]

Answer:

Please red the answer below

Step-by-step explanation:

In order to determine the length of each cable you use the Newton second law for each component of the forces involved in the situation.

For the x component you have:

$T_1cos\theta_1-T_2cos\theta_2=0$ (1)

T1: tension of the first cable = 1500N

T2: tension of the second cable = 800N

θ1: angle between the horizontal and the first cable

θ2: angle between the horizontal and the first cable

For the y component you have:

$T_1sin\theta_1+T_2sin\theta_2-W=0$ (2)

W: weight of the camera = Mg = (140kg)(9.8m/s^2) = 1372N

You can squared both equations (1) and (2) and the sum the two equations:

$T_1^2cos^2\theta_1=T_2^2cos^2\theta_2\\\\T_1^2sin^2\theta_1=T_2^2sin^2\theta_2-2WT_2sin\theta_2+W^2$

Then, you sum the equations:

$T_1^2(cos^2\theta_1+sin^2\theta_1)=T_2^2(sin^2\theta_2+cos^2\theta_2)-2Wsin\theta_2+W^2$ (3)

Next, you use the following identity:

$sin^2\theta+cos^2\theta=1$

and you obtain in the equation (3):

$T_1^2=T_2^2-2WT_2sin\theta_2+W^2\\\\sin\theta_2=\frac{T_2^2-T_1^2+W^2}{2WT_2}=\frac{(800N)^2-(1500)^2+(1372N)^2}{2(800N)(1372N)}=0.066\\\\\theta_2=sin^{-1}0.066=27.23\°$

With this values you can calculate the value of the another angle, by using the equation (1):

$\theta_1=cos^{-1}(\frac{T_2cos(27.23\°)}{T_1})=cos^{-1}(\frac{(800N)(cos27.23\°)}{1500N})\\\\\theta_1=61.69\°$

Now, you can calculate the length of each cable by using the information about the width of the football field. You use the following trigonometric relation:

$l_1cos\theta_1=40-d\\\\l_2cos\theta_2=d\\\\$

d: distance to the right side of the field

By using the cosine law you can fins a system of equation and then you can calculate the values of l1 and l2.

3 0

3 years ago