# RS Aggarwal Class 8 Math Eleventh Chapter Compound Interest Exercise 11C Solution

**EXERCISE 11C**

**(1) Find the amount and the compound interest on Rs 8000 for 1 year at 10% per annum, compounded half-yearly.**

Solution: Here, principal = Rs 8000, rate = 10% p.a. = 5% per half-year.

Time = 1 year = 2 half years

∴ Compound interest = Rs (8820 – 800) = Rs 820.

**(2) Find the amount and the compound interest on Rs 31250 for 1(1/2) years at 8% per annum, compounded half-yearly.**

Solution: Here, principle = Rs 31250, rate = 8% per annum = 4% per half-

∴ Compound interest = Rs (35152 – 31250) = Rs 3902.

**(3) Find the amount and the compound interest on Rs 12800 for 1 year at 7(1/2)% per annum, compounded semi-annually.**

Solution: Here, principal = Rs 12800; Time = 1 year = 2 half-years;

∴ Compound interest = Rs (13778 – 12800) = Rs 978

**(4) Find the amount and the compound interest on Rs 160000 for 2 years at 10% per annum compounded half-yearly.**

Solution: Here, principal = Rs 160000; rate = 10% per annum = 5% per half-year; Time = 2 years = 4 half years.

∴ Compound interest = Rs (194481 – 160000) = Rs 34481.

**(5) Swati borrowed Rs 40960 from a bank to buy a piece of land. If the bank charges 12(1/2)% per annum, compounded half-yearly, what amount will she have to pay after 1(1/2) years? Also, find the interest paid by her.**

Solution: Here, principal = Rs 40960;

∴ Compound interest = Rs (49130 – 40960) = Rs 8170.

**(6) Mohd, Aslam purchased a house from Avas Vikas Parishad on credit. If the cost of the house is Rs 125000 and the Parishad charges interest at 12% per annum compounded half-yearly, find the interest paid by Aslam after a year and half.**

Solution: Here, principle = Rs 125000; rate = 12% per annum = 6% per half-year;

∴ Compound interest = Rs (148877– 125000) = Rs 23877.

**(7) Sheela deposited Rs 20000 in a bank, where the interest is credited half-yearly. If the rate of interest paid by the bank is 6% per annum, what amount will she get after 1 year?**

Solution: Here, principle = Rs 20000, rate = 6% per annum = 3 % per half year, time = 1 year = 2 half years

∴ Compound interest = Rs (21218 – 20000) = Rs 1218

** (8) Neeraj lent Rs 65536 for 2 years at 12(1/2)% per annum, compounded annually. How much more could he earn if the interest were compounded half-yearly?**

Solution: Here, principle = Rs 65536; time = 2 years = 4 half-years;

∴ Compound interest = Rs (83521 – 65536) = Rs 17985

When, the interest is compounded yearly is given by,

= Rs 82944

∴ Compounded interest = Rs (82944 – 65536) = Rs 17408

Therefore, difference between half yearly and yearly = Rs (17985 – 17408) = Rs 577.

**(9) Sudershan deposited Rs 32000 in a bank, where the interest is credited quarterly. If the rate of interest be 5% per annum, what amount will he receive after 6 months?**

Solution: Here, principal = Rs 32000; Time = 6 months = 2 quarter years;

**(10) Arun took a loan of Rs 390625 from, Kuber Finance. If the company charges interest at 16% per annum, compounded quarterly, what amount will discharge his debt after one year?**

Solution: Here, principle = Rs 390625; rate = 16% per annum = 4% per quarter-years, Time = 1 year = 4 quarter-years