Question

The balance in will's mastercard account grew 2%, to $870, in one month. What was his balance at the beginning of the month?

Answer 1

Is this annuity?

Answer 2

OR compound interest? Or neither?

Answer 3

let x = orig amt.

x + 2% x = 870
x + .02x = 870
multiply both sides by 100 to get rid of the decimal

100x + 2x = 87000

102x = 87000

can you do it from there?