Answer:
Return on investment ≈ 29%
Step-by-step explanation:
using excel function
Determine :
Rate = 7% / 12 = 0.0058
Nper value = 30 years * 12 = 360
PV = -$150,000
∴ PMT value = $997.95
next : calculate the outstanding balance 15 years later
= ( 997.95 / 0.00583 ) * ( 1 - ( 1 / ( 1 + 0.00583 )^15*12 ))
= 171174.96 * 0.6489
= $ 111,075.43
Considering the opportunity to refinance
Rate = 6% /12 = 0.005
Nper = 15 * 12 = 180
Pv = - $111,075.43
∴ PMT = 937.32
the monthly saved up payment = PMT 1 - PMT 2
= 997.95 - 937.32 = $60.63
Finally
Rate of return on investment
= 2500 = 60.63 *
hence Rate of return ≈ 29 %
attached below is a screenshot of the excel function used for question 2 and it can be used for question 1 as well just change the values