The distance, d, through which a stone falls from rest varies directly as the square of the time, t, taken. If
the stone falls 45cm in 3 seconds, how far will it fall in 6
seconds?

180 cm

Explanation:

d = t2 k

where k is a constant. d = 45cm, when t = 3s; thus 45 = 32 x t

k = 459 = 5

thus equation connecting d and t is d = 5t2

when t = 6s, d = 5 x 62

= 5 x 36

= 180cm

answer; analytical,creative and practical;