The cost of living in a certain city rose 20% between 1960 and 1970, and rose 50% between 1960 and 1980. By what percent did the cost of living increase between 1970 and 1980?

1.A painter used one-fourth of her paint on one room and one-third of her paint on a second room. If she had 10 gallons of paint left after painting the second room, how many gallons did she have when she began?

2.If the population of Town B is

3.The difference of two numbers is

4.If the ratio of

5.The average (arithmetic mean) of seven integers is

6.

7.The first term in a sequence is

8.If a, b and c are positive even integers such that

9.One bag of grass seed cover 5,000 square feet. If each bag cost BDT 25; how much will it cost to buy enough grass seed to cover a square area that is

10.1, 2, 6, 7, 9: A 3-digit integer is to be formed from the digits listed above. If the first digit must be odd, either the second or the third digit must be 2, and no digit may be repeated, how many such integers are possible?

11.If

12.The difference of two integers is