Question

If D varies directly with t and D is 105 when t is 3, find D when t is 8.

35
280
840

Answer 1

@Ultrilliam

Answer 2

Direct variation means that D = kt where k is a constant
to find k plug in the given values of D and t:-
105 = k*3
k = 105 / 3 = 35

o we have D = 35t

when t = 8
D = 35*8 = 280