WAEC - Mathematics (1997 - No. 10)
P varies inversely as the square of W. When W = 4, P = 9. Find the value of P when W = 9
729/16
6
4
16/9
4/3
Explicación
P α 1/w2; P = K/W2
9 = K/42; 9 = K/16
K = 9 x 16 = 144
P = K/W2; when w = 9
P = 144/92 = 144/81 = 16/9
9 = K/42; 9 = K/16
K = 9 x 16 = 144
P = K/W2; when w = 9
P = 144/92 = 144/81 = 16/9