Question

quantities x and y are inversely proportional when x=8, y=25 find the value of y when x=10

Answer 1

x1/x2 =y2/y1
8/10=y2/25
4/5 =y2/25
4=y2/5
y2=5×4=20 is answer

Answer 2

Given, X is inversely proportional to Y

then ,

X = K / Y ------eq.(1)

where k is a constant .

K = X Y

here X = 8 , and Y = 25

K= 8 × 25 = 200

K = 200

now put value of " K " in eq. (1) , we get

now the equation is

X = 200 / Y

here , given X = 10

10 = 200 / Y

Y = 200 / 10 = 20

Y = 20

hence, the value of " Y" is 20.