As per agreement with a bank, a businessman had to refund a loan in some equal instalments without interest. After paying 18 instalments he found that 60 percent of his loan was refunded. How many instalments were there in the agreement ?
- (a) 22
- (b) 24
- (c) 30 ✓ UPSC's answer
- (d) 33
Why the answer is (c)
• Let the total number of equal instalments be n.
• Since instalments are equal and without interest, each instalment refunds 1/n of the loan.
• After 18 instalments, the refunded amount is 18/n of the loan.
• This is given as 60 percent, so 18/n = 60/100 = 3/5.
• Solving gives n = 18 × 5/3 = 30.
• Therefore, the agreement had 30 instalments, which is option (c).
Why the other options are wrong
- (a) 22
- Option (a) 22 would make 18 instalments equal to 18/22, not 3/5 or 60 percent.
- (b) 24
- Option (b) 24 would make 18 instalments equal to 18/24, i.e. 3/4 or 75 percent, not 60 percent.
- (d) 33
- Option (d) 33 would make 18 instalments equal to 18/33, i.e. 6/11, not 3/5 or 60 percent.
Asked in the CSAT Paper II of the UPSC Civil Services Preliminary Examination 2014, held on 24 August 2014. Question and answer key: Union Public Service Commission. Explanation: UPSC Answer Check.