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3 years ago

A school has 20% of girls and 160 boys, how many kids are in the school?

Mathematics

1 answer:

ioda3 years ago

8 0

Answer:

200

Step-by-step explanation:

20%=girls

=100%-20%

80%=boys

80%/100×y=160

=160÷80%/100

=160×100/80

=200

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Express the following as sum of partial fraction.-3x + 15 divided by (x + 1 )( x -2)2 squared

cestrela7 [59]

Answer:

why

explanation:

no

6 0

4 years ago

A 29-meter ladder is sliding down a vertical wall so the distance between the top of the ladder and the ground is decreasing at

vitfil [10]

Complete question

A 29-meter ladder is sliding down a vertical wall so the distance between the top of the ladder and the ground is decreasing at 7 meters per minute. At a certain instant, the bottom of the ladder is 21 meters from the wall.

What is the rate of change of the distance between the bottom of the ladder and the wall at that instant(in meters per minute)

Answer:

$\frac{dx}{dt}=11.94m/min$

Step-by-step explanation:

From the question we are told that

Slant height $z=29m$

Change in Vertical height $\triangle y=7m/s$

Horizontal length $x=21$

Generally in finding the distance form the top to the bottom of the wall it is mathematically given by

$x^2+y^2=z^2$

$21^2+y^2=29^2$

$y^2=29^2+21^2$

$y=35.81$

Generally solving for the differential equation is mathematically represented as

$x^2+y^2=29^2$

$2x*\frac{dx}{dt} +2y*\frac{dy}{dt} =0$

$x*\frac{dx}{dt} +y*\frac{dy}{dt} =0$

$(21)*\frac{dx}{dt} +(35.81)*(-7) =0$

$(21)*\frac{dx}{dt} -250.64 =0$

$\frac{dx}{dt}=\frac{250.64}{21}$

$\frac{dx}{dt}=11.94m/min$

5 0

3 years ago

I have a two expressions 3z-4 and 2z+5

aleksley [76]

Answer:

The answers are 3z-16 and 2z+10

Step-by-step explanation:

Do 3 x z (3z) and then do 3 x 4 (16) and then you got 3z-16

Do 2 x z (2z) and then do 2 x 5 (10) and then you got 2z + 10

6 0

3 years ago

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Leto [7]

Answer:

3mg per BID vistrail

Step-by-step explanation:

7 0

3 years ago

HELP HELP PLEASE!! D:<br><br> Determine the missing side length:<br> Please don't give cap!

viktelen [127]

Answer:

c = 35

Step-by-step explanation:

$c^{2} = a^{2} + b^{2}$

$c^{2} = 21^{2} + 28^{2}$

$c^{2} = 1225$

$\sqrt{c^{2} } = \sqrt{1225}$

$c = 35$

8 0

3 years ago