Compound Interest (notes)

Compound Interest

​earnings paid on the principal and the accumulation of interest from previous periods.

​Formula:

​A=P(1+r)^t

​A = amount

Total balance​

​P = principal

Amount of money started with ($)​

​R = rate

(%) as a decimal​

​T = time

Time in years​

​Ex. 1) Rachel deposited $10 in an account earning 5% interest compounded annually. To the nearest cent, how much will she have in 3 years?

​A=P(1+r)^t

​

A=

​

A=​

Fill in the Blanks

Ex. 2) Spencer deposited $18 in an account earning 4% interest compounded annually. To the nearest cent, how much will he have in 9 years? (DO NOT put a $ or a comma)

Fill in the Blanks

Ex. 3) Andy has $1,000 in an account. The interest rate is 15% compounded annually. To the nearest cent, how much will he have in 2 years? (DO NOT put a $ or a comma)

​Ex. 4) Brooke has $7 in an account that earns 10% interest compounded annually. To the nearest cent, how much interest will she earn in 2 years?

​A=P(1+r)^t

​

A=

​

A=​

​Interest earn(ed) = A - P

​

I =

​

I =​

Fill in the Blanks

Ex. 5) Ayana has $730 in an account. The interest rate is 3% compounded annually. To the nearest cent, how much interest will she earn in 3 years? (DO NOT put a $ or a comma)

Fill in the Blanks

Ex. 6) Nina has $63,071.45 in an account. The interest rate is 14% compounded annually. To the nearest cent, how much will be her interest in 5 years? (DO NOT put a $ or a comma)