Question

Martin deposits $200 in a savings account that earns 5% annual interest. Four years later, Cary deposits

$200 in an account earning the same interest. Let M represent the balance in Martin's account and let C
represent the amount of money in Cary's account.
Choose the pair of expressions that describe the
accounts y years after Martin opened his account.

Answer 1

200 + (10 y)

Explanation:

martin 200 * 5 and divide by 100 =10 per year interest 240 =M

cary 200 + 10=210 =C

200 + (10 y)

Answer 2

Martin: 200(1.05)^y

Cary: 200(1.05)^y-4

M=1.22C