Exponential Functions word problem

Question

A 529 Plan is a college-savings plan that allows relatives to invest money to pay for a child's future college tuition; the account grows tax-free. Lily wants to set up a 529 account for her new granddaughter and wants the account to grow to $48,000 over 20 years. She believes the account will earn 4% compounded quarterly. To the nearest dollar, how much will Lily need to invest in the account now?

 

A(t)= P(1+r/n)^nt

 

Lily need to invest ________

Answer 1

Amount in the Account=Amount invested∗(1+r⁄n)∧nt

Amt after 20 years=$48000

Amt invested=P

r=interest rate

n=number of compounds annually

t=time

48000=P(1+.04/4)∧4∗20

48000=P(1.01)∧4∗20

48000=P(2.217)

P=48000/2.217

P=$21653.70