Jackson just got a 30-year mortgage, and plans to pay $200 toward the principal each month. To pay the mortgage off 10 years early, how much more money does he have to pay on the principal each month? (Do not consider interest expense in your response).

A.400
B.300
C.100
D.none of the above

Question

Jackson just got a 30-year mortgage, and plans to pay $200 toward the principal each month. To pay the mortgage off 10 years early, how much more money does he have to pay on the principal each month? (Do not consider interest expense in your response).
 
A.400 
B.300
C.100 
D.none of the above

saifoo.khan · Answer

What we want to know is the amount in 30 year of principal interest. This is simply the number 30*200. Now we want to pay all this off in 10 years, so similarly,

30*200 = 10*p

where p is the amount he has to pay each month. However, the question asks how much MORE, which means the answer will be p - 200 (the difference).