Answer: The amount in the account is A = A(1 + P/400)^20
Explanation:
Initial amount deposited into the account is A. This means that the principal is A, so
P = A
It was compounded quarterly. This means that it was compounded once in four months. So
n = 4
The rate at which the principal was compounded is P%. So
r = P/100
It was compounded for a total of 5 years. So
n = 5
The formula for compound interest is
A = P(1+r/n)^nt
A = total amount in the account at the end of n years.
Let A = B
B = A(1 + (P/100)/4)^4Ă—5
A = A(1 + P/400)^20