Question

On January 1, 1970, Lois deposited $1950 into a savings account paying 6.6% interest, compounded semiannually. If she hasn't made any additional deposits or withdrawals since then, and if the interest rate has stayed the same, in what year did her balance hit $3900, according to the rule of 72?

A. 1979
B. 1981
C. 1982
D. 1980

Answer 1

hey was the last answer correct, 8.2 years?

Answer 2

yes it was thanks @perl

Answer 3

awesome :)

Answer 4

so it takes 72/6.6 years to double your money at 6.6% annual interest.
that is equal to 10.9 years or about 11 years.
Add 11 to 1970

Answer 5

which makes 1981

Answer 6

yaaaaay @perl