P varies inversely as the square of W. When W = 4, P = 9. Find the value of P when W = 9
- A.
729/16 - B.
6 - C.
4 - D.
16/9 - E.
4/3
Correct Answer: Option D
Explanation
P α 1/w^{2}; P = K/W^{2}
9 = K/4^{2}; 9 = K/16
K = 9 x 16 = 144
P = K/W^{2}; when w = 9
P = 144/9^{2} = 144/81 = 16/9