Answer:
31
Step-by-step explanation:
it said 22 2's , so 22 + 9
and 0,1,3,4,5,6,7,8,9 is 9 numbers
1
7 x 1 = 7
hope this helps!
John's effective annual rate is about
(1 +.0576/4)^4 -1 ≈ 5.8856%
According to the "rule of 72", John's money will have doubled in
72/5.8856 = 12.23 years
John's balance will be $4500 in 1989.
_____
Since you're only concerned with the year (not the month), you don't actually need to determine the effective annual rate. The given rate of 5.76% will tell you 72/5.76 = 12.5 years. The actual doubling time is closer to 12.12 years, so using the effective rate gives results that are closer, but "good enough" is good enough in this case.
