Respuesta :
You are told to ignore the amount of principal paid, so you are apparently to assume the loan amount was for $50 thousand.
a) The old monthly payment was $10.67×50 = $533.50
b) The new monthly payment is $11.72×50 = $586.00
c) The increase in monthly payment is figured in the usual way:
... (new/old -1)×100% = (1.0984-1)×100% = 9.84%
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In reality, about 3% of the loan will have been paid at the end of 2 years. Thus, the original loan amount may have been near $51,500. This problem is telling you to ignore the difference.
Remark
The first fact you need to know is that the bank has taken money from you and nothing has been reduced from the principle. Crafty people those bankers; you are going to pay off the interest before touching the principle. They're like you to refinance for the rest of your life at the rates you currently have.
Point. You started out with a 50k debt. You still have that same debt.
Solution
Givens
number of thousands (n) = 50000/1000 = 50
Amount paid per thousand (A) = 10.67
Total monthly payments (T) = ?
Part A
T = n * A
T = 50 * 10.67
T = 533.50 is the old monthly payment
Part B
T = n * A
T = 50 * 11.72
T = 586.00 new monthly payment.
Part C
This is a notes question. What have you been told in your notes on this question. You can find the raw amount just by subtracting 586 - 533.50 = 52.50
But how do you find the % increase. Which one of the payments do you use as your base?
In point of fact, you should be using the first number 533.5
What % will you get when you multiply that by 533.5 and get 52.50?
You are not trying to find 586. You are trying to find the number that you add to 533.5 to get to 586
The answer is (52.50 / 533.5)*100% = 9.84% is the % increase.