Question
The amount of a certain sum in 3 years at simple
interest at x % p.a. is ₹5,472 and the amount of the same sum in 7(1/2) years at the same rate, at simple interest is ₹6,930. The value of x is:Solution
Let the sum be Rs. p. According to the question, p + (p × x × 3)/100 = 5472 ....(1) According to the question, p + (p × x × 7.5)/100 = 6930 ....(2) (2) - (1) we get, p + (p × x × 7.5)/100 - p - (p × x × 3)/100 = 6930 - 5472 ⇒ 7.5xp/100 - 3xp/100 = 1458 ⇒ 4.5xp/100 = 1458 ⇒ xp = 145800/4.5 ⇒ xp = 32400 ....(3) Putting xp = 32400 in (2), p + (p × x × 7.5)/100 = 6930 ⇒ p + (32400 × 7.5)/100 = 6930 ⇒ p = 6930 - (32400 × 7.5)/100 ⇒ p = 6930 - 2430 ⇒ p = 4500 ....(4) Putting p = 4500 in (3), x × 4500 = 32400 ⇒ x = 32400/4500 ⇒ x = 7.2 ∴ The value of x is 7.2.
A sum of money amounts to Rs 9,200 in 3 years at 5% simple interest per annum. Find the interest earned .
A and B started a business with initial investments of Rs. 30000 and Rs. 40000 respectively. After one year, a profit of Rs. 8000 is earned. A being a w...
The simple interest received on a certain sum is Rs. 500 less than the sum invested. If the sum was invested at 12% p.a. for 8 years, then find the simp...
- Neha deposited Rs. 3000 at (R + 6)% per annum simple interest and received Rs. 2160 as interest in 3 years. What would be the interest if she invested the ...
A man invested Rs. 'D' at simple interest of 22% and Rs. 'D + 5000' at simple interest of 18% p.a., for 2 years each. If the interest earned from both i...
A certain amount doubles itself when invested at r% p.a. simple interest for 10 years. Find the value of r.
A certain sum of money becomes 5000 in 6 years and Rs. 6240 in 10 years at any certain rate of simple interest. Find the principal amount.
An amount of Rs. 2400 is placed in SIP 'P' at a 25% per annum simple interest rate for 8 years, and Rs. 2500 is invested in SIP 'Q' with a 20% annual co...
A man invested certain sum at 7.5% p.a. simple interest for his son who was 11 years old. If the amount received by the son when he was 22 years old is ...
A sum of ₹7500 becomes ₹8850 in 3 years at simple interest. Find the rate of interest per annum.