1. A reduction of 20% in the price of rice enables a customer to purchase 12.5 kg more for ₹ 800. The original price of rice per kg is

₹ 15

₹ 14

₹ 16

₹ 12

2. In two alloys A and B, the ratio of zinc to tin is 5: 2 and 3 : 4 respectively. Seven kg of the alloy A and 21 kg of the alloy B are mixed together to form a new alloy. What will be the ratio of zinc and tin in the new alloy?

1 : 1

2 : 1

1 : 2

2: 3

3. If the graphs of the equations x + y = 0 and 5y + 7x = 24 intersect at (m, n), then the value of m + n is

–1

2

1

0

4. The average age of a class of 35 students is 15 years. If the teacher's age is also included the average age increased by one year. Furthermore, if the average age of the teacher's family having a wife and a son is 40 years and the son's age is 80% less than his mother's age, then the age of the teacher's wife is

55.5 years

57.5 years

50 years

47.5 years

5. A shopkeeper sells an article at 15% gain. Had he sold it for ₹ 18 more, he would have gained 18%. The cost price (in ₹ ) of the article is

350

540

318

600