Answer:
$38,645.7208
Step-by-step explanation:
Given that
Principal = $70,000
Time = 20 years
Rate = 2.2%
The calculation of the amount of saving is shown below:-

A = Future amount
P = Principal amount

0.001833333
t = 20 years which is equals to 240 months


= $108,645.7208
And, the loan amount for 20 years is $70,000
So,
He would save by paying off 9 years early is
= $108,645.7208 - $70,000
= $38,645.7208