Question
If the average cost price of 20 identical pens decreases
by Rs. 2 after replacing one pen with a new pen that costs Rs. 80, what was the original cost price of the replaced pen?Solution
ATQ;
Let the cost price of each pen be Rs. 'x'
So, cost price of 20 pencils = Rs. 20x
ATQ;
(20x - x + 80) ÷ 20 = x - 2
Or, 19x + 80 = 20x - 40
Or, x = 120
So, cost price of the pen that was removed is Rs. 120.
If an amount of Rs. 'x' is invested at an annual compound interest rate of 20%, it grows to Rs. 'x + 2200' after 2 years. Calculate the value of 'x + 22...
Rs. P invested at R% p.a. gives simple interest and compound interest (compounded annually) of Rs. 640 and Rs. 665.60 respectively at the end of 2 years...
The amount becomes ₹ 1,451.25 in one year on a simple rate of interest. If the rate of interest was 2% higher, the amount would have been ₹ 27 more...
Sohan gave Rs. 5000 to Ramesh on simple interest at 12% per annum. After 3 years, he invested the total money received from Ramesh in a plan giving comp...
- A man deposits Rs. 36,000 at a simple interest rate of 25% per annum. What will be the total amount after 30 months?
A man deposited Rs. 9000 at 10% compound interest, compounded annually while Rs. 8500 at 13% simple interest per annum. What will be the difference betw...
Rs.26000 is split into two sums such that the Simple Interest on one part for 5 years at 10% equals the Simple Interest on the other part for 6 years at...
A sum of Rs. 9,600 grows to Rs. 12,696 when invested at an annual compound interest rate of 'R%' for 2 years. What is the value of 'R'?
Mr. P invested Rs. ‘10x’ in scheme ‘A’ offering simple interest of 20% p.a. and reinvested the interest earned from scheme ‘A’ at the end of...
Simple interest earned on an amount of Rs. 1250 at rate of R% per annum after 4 years is Rs. 250. Find the simple interest earned on an amount of Rs. 13...