Given-
Annual interest rate = 5%
By using the rule of 72,
Rate x Time = 72
Rate = 5%
t = ?
So,
5 x t = 72
5t = 72
Isolate t by dividing both sides by 5 :-
→ 5t/5 = 72/5
→ t = 14.4 years
Hence, it will take 14.4 years for the deposit to double at 5% annual rate.
✍️ By Benjemin ☺️
