Advertisements
Advertisements
प्रश्न
Find the rate of compound interest at which a principal becomes 1.69 times itself in 2 years
Advertisements
उत्तर
Let principal be ‘P’
Amount is given to be 1.69 times principal
i.e 1.69 P
Time period is 2 years. = (n)
Rate of interest = r = ? ...(required)
Applying the formula,
Amount = `"Principal" (1 + "r"/100)^"n"`
Substituting 1.69 P = `"P"(1 + "r"/100)^2`
∴ `(1 + "r"/100)^2 = (1.69"P")/"P"` = 1.69
Taking square root on both sides, we get
`sqrt(1.69) = 1 + "r"/100`
∴ `1 + "r"/100` = 1.3
∴ `"r"/100` = 1.3
r = 30%
∴ rate of compound interest is 30%
APPEARS IN
संबंधित प्रश्न
What will Rs 125000 amount to at the rate of 6%, if the interest is calculated after every 3 months?
The present population of a town is 28000. If it increases at the rate of 5% per annum, what will be its population after 2 years?
A certain sum amounts to Rs. 5,292 in two years and Rs. 5,556.60 in three years, interest being compounded annually. Find : the rate of interest.
The value of a machine depreciated by 10% per year during the first two years and 15% per year during the third year. Express the total depreciation of the machine, as percent, during the three years.
Ashok borrowed Rs. 12,000 at some rate on compound interest. After a year, he paid back Rs.4,000. If the compound interest for the second year is Rs. 920, find:
- The rate of interest charged
- The amount of debt at the end of the second year
On a certain sum of money, lent out at C.I., interests for first, second and third years are Rs. 1,500; Rs. 1,725 and Rs. 2,070 respectively. Find the rate of interest for the (i) second year (ii) third year.
Peter borrows ₹ 12,000 for 2 years at 10% p.a. compound interest. He repays ₹ 8,000 at the end of the first year. Find:
- the amount at the end of the first year, before making the repayment.
- the amount at the end of the first year, after making the repayment.
- the principal for the second year.
- the amount to be paid at the end of the second year, to clear the account.
A certain sum of money invested for 5 years at 8% p.a. simple interest earns an interest of ₹ 12,000. Find:
(i) the sum of money.
(ii) the compound interest earned by this money in two years and at 10% p.a. compound interest.
The simple interest on a certain sum of money at 4% p.a. for 2 years is Rs1500. What will be the compound interest on the same sum for the same time?
The time taken for ₹ 4400 to become ₹ 4851 at 10%, compounded half yearly is _______
