Question

A gym currently has
3
,
645
members. The gym started with
5
members, and membership has tripled each month for
x
months.



Which equation represents the gym membership after
x
months?



A.
4
(
5
)
x
=
3645

B.
3
(
5
)
x
=
3645

C.
5
(
4
)
x
=
3645

D.
5
(
3
)
x
=
3645

Answer 1

D. The number after x months is initial × growth^x, so 5·3^x = 3645. (Check: 3^6 = 729 and 5·729 = 3645, so x = 6.)