Question

3/8 of the people at a restaurant are adults. If there are 90 more children than adults, how many children are there?​

Answer 1

Let the total people at the restaurant be x

Adults=(3/8) x

Children=(3/8)x +90

Total people =Total adults +Total children

x=3x/8 +3x/8 +90

x=2(3x)/8 +90

x=3x/4 +90

x-3x/4=90

4x-3x=4×90

x=360

So total people =360

children =3x/8 +90 =3×360/8 +90=225 ans

Answer 2

Let the total number of people in restaurant be x

3/8 of people = Adults = 3x/8

90 more than children = Children = 3x/8 + 90

Total people = Adults + Children

$x = \frac{3x}{8} + \frac{3x}{8} + 40$

$x = \frac{6x}{8} + 90$

$x = \frac{6x}{8} + \frac{90 \times 8}{1 \times 8}$

$x = \frac{6x}{8} + \frac{720}{8}$

$x = \frac{6x +720}{8}$

$8x = 6x + 720$

$8x - 6x = 720$

$2x = 720$

$x = \frac{720}{2}$

$x = 360$

Total number of people = x = 360

Children = 3x/8 + 40 = 3(360)/8 + 90 = 1080/8 + 90 = 135 + 90 = 225

Therefore the number of children are 225.