Total number of installments = 52
Payment per installment for the first 20 installments = 410
Payment per installment for the remaining 32 installments = 410+65=475
Average = (20*410 + 32*475)/52 =(8200+15200)/52=23400/52 = 450
Answer B
Alternatively , we can proceed as -
65 is difference in value between payment per installment in first 20 installments and the payment per installment for the remaining 32 installments.
At this point we can eliminate option A and E .
(Option A= 443 - If the number of installments were in equal proportion , then average would have been = (410+475)/2=442.5
Option E = 475 - It would be true if all the installments were of 475 )
Number of installments are in the ratio = 20/32 = 5/8
Total number of parts = 5+8 = 13
We need to divide 65 into 13 parts , and the parts will be 25 and 40 . And the distances will be in inverse proportion
Therefore 410 +40 = 450
Answer B
_________________
When everything seems to be going against you, remember that the airplane takes off against the wind, not with it. - Henry Ford
The Moment You Think About Giving Up, Think Of The Reason Why You Held On So Long