x varies inversely to the square of y. Given that y = 5 when x = 6, find the value of x when y = 4.
Show answer & explanation
Correct answer: C
Explanation
The correct answer is option 3 i.e. 9.375 .
x varies inversely to square of y
So, x = k ÷ y2
When, y = 5, x = 6
6 = k ÷ 52
6 = k ÷ 25
k = 6 × 25 = 150
when, y = 4
x = 150 ÷ 42
x = 150 ÷ 16
x = 9.375