Question

half of herd of deer are grazing in the field and three fourth of the remaining are playing nearby .the test 9 are drinking water from the pond . find the number of deer in the herd?​

Answer 1

$\frac{x}{2} + \frac{3x}{4} + 9 = x \\ \frac{2x + 3x + 36}{4} = x \\ \frac{5x}{4} + 9 = x \\ x - \frac{5x}{4} = 9 \\ \frac{4x - 5x}{4} = 9 \\ 4x - 5x = 9 \times 4 \\ - x = 36 \\ x = - 36 \: answer$

Answer 2

Let the total no of deer be x

So, we have

x−( 21 x+ 43× 21x)=9

x−( 21 x+ 83x)=9x− 87

x=9

81 x=9;

Thus, x=72 deer in the herd..