Question

Rs. 8000 is lent in two parts. A part is lent at 10% p.a. and the other part is lent at 20% p.a. Both parts are lent at simple interest for a year. The total interest realized from them is Rs. 960. Find the difference of the parts (in Rs).
A) 4800
B) 2400
C) 1600
D) 5400

Answer 1

Simple Interest

Given:

• Total amount = Rs. 8000
• Rate of interest for 1st part is 10% p.a.
• Rate of interest for 2nd part is 20% p.a.
• Total interest after 1 year = Rs. 960

To find: difference between the parts

Step-by-step explanation:

• Let the two parts be A and B.

• Interest on A for 1 year at 10% p.a. is
• = Rs. A * 1 * 10 / 100 = Rs. A/10

• Interest on B for 1 year at 20% p.a. is
• = Rs. B * 1 * 20 / 100 = Rs. B/5

• By the given condition,
• A/10 + B/5 = 960
• or, A + 2B = 9600 .....(1)

• Again, since A and B are the only two parts of Rs. 8000, then
• A + B = 8000 .....(2)

• Subtracting (2) from (1), we get
• B = 1600 .....(3)

• Putting B = 1600 in (2), we get
• A + 1600 = 8000
• or, A = 6400

• Now A - B = Rs. (6400 - 1600) = Rs. 4800

Answer: Option A) Rs. 4800