1. The three sides of a triangle are in the ratio 3 : 4 : 6, find the ratio of the three corresponding altitudes.
2. Expenses of a hostel are partly constant and partly vary with number of students. When there are 20 students, total expenses are Rs. 2000. When there are 50 students, total expenses are Rs. 3500. Find the total expenses when there are 70 students in the hostel.
3. A bag contains Rs 216 in the form of one rupee, 50 paise and 25 paise coins in the ratio of 2 : 3 : 4. The number of 50 paise coins is:
4. The salaries of A, B, C are in the ratio 2 : 3 : 5. If the increments of 15%, 10% and 20% are allowed respectively in their salaries then what will be the new ratio of their salaries?
5. The ratio of the number of boys and girls in a college is 7 : 8. If the percentage increase in the number of boys and girls be 20% and 10% respectively. What will be the new ratio?
6. Divide Rs 671 among A, B, C such that if their shares be increased by Rs 3, Rs 7 and Rs 9 respectively, the new shares shall be in the ratio 1 : 2 : 3.
7. A and B are two alloys of gold and copper prepared by mixing metals in the ratio 7 : 2 and 7 : 11 respectively. If equal quantities of the alloys are melted to form a third alloy C, the ratio of gold and copper in C will be:
8. A contractor employed 25 laborers on a job. He was paid Rs 275 for the work. After retaining 20% of this sum, he distributed the remaining amount amongst the laborers. If the number of male to female laborers was in the ratio 2 : 3 and their wages in the ratio 5 : 4, what wages did a female laborer get?
9. If the cost of using air conditioner is directly proportional to the time for which it is used, inversely proportional to the number of stars given to it and directly proportional to its power in terms of tonns. It cost Rs 150 if a 2 star air conditioner of 2 tonns is used for 10 hrs. Then how much will it cost if a 3 star air conditioner of 1.5 tonns is used for 8 hours.
10. The cost of etching a glass with design varies directly as the square of its area. It will cost Rs. 8000 to etch a glass plate of 1m × 1m dimension. What would be the loss to the artist if he were to etch 4 pieces of dimension 1/2 m × 1/2 m instead of the 1m × 1m piece?