The total loan amount equal in four years when he graduates is $14,310.22.
Using this formula
A=P(1+r)^t
Where:
A= Amount=?
P=Principal=$12,000
r =interest rate=4.5%
t =Time=4 years
Let plug in the formula
Amount=12,000(1+0.045)^4
Amount=12,000(1.045)^4
Amount=12,000(1.1925)
Amount=$14,310.22
Inconclusion the total loan amount equal in four years when he graduates is $14,310.22.
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