- Gunpowder contains 75% Nitre and 10% Sulphur. Find the amount of gunpowder which carries 9 kg Nitre. What amount of gunpowder would contain 2.5kg sulphur? (12kg, 25kg)
- If the cost price of 10 cards is equal to the selling price of 8 cards, find the gain or loss percent. (25%Gain)
- By selling 33m of cloth, a draper loses an amount equal to the selling price of 3m of cloth. Find his gain or loss percent. (81/3 % loss)
- By selling a T-shirt for Rs.432, a shopkeeper loses 4%. For how much should he sell it to gain 6%? ( 477)
- Harsh sold a bicycle at 8% gain. Had it been sold for Rs.75 more, the gain would have been 14%. Find the CP. (1250)
- Sam sells two watches for Rs. 1955 each, gaining 15% on one and losing 15% in the other. Find the gain or loss percent in the whole transaction. ( 21/4 % loss )
- A reduction in the price of sugar enables Mr.Sam to buy an extra 3kg of it for Rs. 360. Find (i) the original rate (30/kg)
(ii) the reduced rate per kg ( 24/kg)

- A dealer purchased a washing machine for Rs.7660. He allows a discount of 12% on its
marked price and still gains 10%. Find the marked price of the machine. (9575)

- How much percent above the cost price should a shopkeeper mark his goods so that
after allowing a discount of 25% on the marked price, he gains 20%? (60%)

- Find the single discount equivalent to two successive discounts of 20% and 10%. (28%)
- Raman bought an air cooler for Rs.5400 including VAT at 8%. Find the original price of
the air cooler. (5000)

- Find the amount of Rs.50,000 after 2 years, compounded annually; the rate of interest being 8%p.a during the first year and 9%p.a during the second year. Also find the C.I. (58860, 8860)
- Find the compound interest on Rs.31250 at 8% per annum for 23/4 years. (7387)
- The simple interest on a sum of money for 3 years at 12% per annum is Rs.6750. What
will be the compound interest on the same sum at the same rate for the same period,

compounded annually? (7592.40)

40. The difference between the C.I and the S.I on a certain sum for 2 years at 15% per

annum is Rs.180. Find the sum. (8000)

- In what time will Rs. 1000 amount to Rs.1331 at 10% p.a, compounded annually? (3yrs)
- The population of a town was 176400 in 2009. It increases at 5% per annum.
- (i) What will be the value in 2011? (194481)
- (ii) What was the value in 2007? (160000)

- In a certain experiment, the count of bacteria was increasing at the rate of 2.5% per
hour. Initially, the count was 512000. Find the bacteria at the end of 2 hours. (537920)

- In a fort, 300 men had provisions for 90 days. After 20 days, 50 men left the fort. How
long would the food last at the same rate? (84 days)

- A pole 14m high casts a shadow of 10m. At the same time, what will be the height of a
tree, the length of whose shadow is 7m? (9.8m)

- To complete a work, A takes 50% more time than B. If together they take 18 days to
complete the work, how much time will B take to complete it alone? (30 days)

- 3 men or 5 women can do a work in 12 days. How long will 6 men and 5 women take to
do it? ( 4 days)

- Find the greatest 4 digit number which is a perfect square. ( 9801)
- If n is odd, (1+3+5+7 … +n) is equal to _____ (n2)
- Find the sum of odd number from 1-100. (2500)