Formula for CI

Q.

On a certain sum of money, the difference between the compound interest for a year, payable half-yearly, and the simple interest for a year is Rs. 180/-. Find the sum lent out, if the rate of interest in both the cases is 10% per annum.

Q. Ashima has a Cumulative or Recurring Deposit Account in a bank for 5 years at 9% p.a. At the time of maturity, she gets Rs 51, 607.50. Find the monthly instalment.
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Q. A sum of money doubles itself in 3 years at compound interest, when the interest is compounded annually. In how many years will the sum amount to 16 times of itself?

Q. The difference between the compound interest on a certain sum at the rate of $5\%$ per annum for $2$ years compounded annually and simple interest for the same $2$ years is Rs. $1000$. What is the principal sum?

Q. If in two years time a principal of Rs. 100 amounts to Rs. 121, when the interest at the rate of r% is compounded annually, then the value ofr will be

1. 10.5
2. 10
3. 15
4. 14

Q. The simple interest on a sum of money for $2$ years at $4\%$ per annum is $Rs340$. Find
(i) the sum of money
(ii) the compound interest on this sum for one year payable half yearly at the same rate.

Q. a sum of money becomes Rs 6615 at a compound interest rate of 5% p.a. in 2 years. find the principal at the beginning of the second year.

Q. The compound interest, calculate yearly, on a certain sum of money for the second year is Rs. 880 and for the third year is Rs. 968. Calculate the rate of interest and the sum of money.

Q. A man saves rs.3000 every year and invests it at the end of the year at 10% compound interest and calculate the total amount of his savings at the end of the third year

Q. Q 8. ​On a certain sum, the compound interest in 2 years amounts to Rs 4, 240. If the rates of interest for successive years are 10% and 15% respectively, find the sum.

Q. The difference between CI and SI on a certain sum for $2$ years at $7.5\%$ p.a. is Rs. $360$. Find the sum.

Q. What sum of money will amount to ₹3630 in 2 years at 10 % per annum compound interest?

A: ₹3200	B: ₹3500
C: ₹3000	D: ₹2500

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Q. $Rs.100000$ was invested by Mohan in a fixed deposit $@10\%$ per annum at CI. However every year he was to pay $20\%$ tax on the compound interest. How much money does Mohan has after $3$ years ?

1. $Rs.128414$
2. $Rs.108000$
3. $Rs.126079.2$
4. $Rs.12971.2$

Q. A sum of money at compound interest becomes double of itself in 15 yrs. The rate of interest is

1. 5.1%
2. 5%
3. 4.7%
4. 4.8%

Q. On a certain sum, the compound interest in 2 years amounts to 4240. If the rates of interest for the successive years are 10% and 15% respectively, find the sum.