1. The average weight of 45 students in a class is 52 kg. 5 of them whose average weight is 48 kg leave the class and other 5 students whose average weight is 54 kg join the class. What is the new average weight (in kg) of the class ?
2. A dishonest grocer professes to sell pure butter at cost price, but he mixes it with adulterated fat and thereby gains 25%. Find the percentage of adulterated fat in the mixture assuming that adulterated fat is freely available.
3. Madan pays income tax at the rate of 10%. If his income increased by 10% and his tax rate increase to 15%. His net income would increase by Rs. 350. What is Madan’s income ?
4. The percentage profit earned by selling an article for Rs. 1920 is equal to the percent loss incurred by selling the same article for Rs. 1280. At what price should the article be sold to make 25% profit ?
5. A dealer offers a cash discount of 20% and still makes a profit of 20%, when he further allows 16 articles to a dozen to a particularly sticky bargainer. How much per cent above the cost price were his wares listed ?
6. The difference between the simple interest received from two different sources on Rs. 1500 for 3 years is Rs. 13.50 . The difference between their rates of interest is:
7. The ratio of the price of two houses A and B was 4 : 5 last year. This year, the price of A is increased by 25% and that of B by Rs. 50000. If their prices are now in the ratio 9 : 10, the price of A last year was :
respectively for the last year.
8. Two pipes can fill a cistern in 6 minutes and 7 minutes respectively. Both the pipes are opened alternatively for 1 minute each. In what time will they fill the cistern.
9. Raju can do a piece of work in 10 days, Vicky in 12 days and Tinku in 15 days. They all start the work together, but Raju leaves after 2 days and Vicky leaves 3 days before the work is completed. In how many days is the work completed ?
10. A plane left 30 min later than its scheduled time to reach its destination 1500 km away. In order to reach in time it increases its speed by 250 km/hr. What is its original speed ?
dipanshu sahu