Hands-on math!

Washington State Math Olympiad
Hints and Solutions
2007 Grade 7 Number Sense
Problem

1) Express 0.0000000056 ÷ 0.00000024 as a fraction in lowest terms.
2) The fraction 11/14 is fairly close to 1. How many fractions are there between 11/14 and 1 that have a prime number denominator smaller than 14?

3) Joe mixes sodas to make the Joe Special. A Joe Special has 2 parts cola to 3 parts orange soda to 3 parts cream soda. If he's going to fill a 64 ounce bottle with his soda special, how many ounces of cola will he need?

Problem
4) The length of a picture is enlarged by 50% and the width is enlarged by 25% producing an odd looking picture. By what percent is the area enlarged? Express your answer to the nearest tenth of a percent. (Hint: you can choose any dimensions that are easy for you to work with.)

5) Jerri has 63⁄4 yard of rope. He needs pieces that are 12⁄3 yards long to make belts for costumes. How many belts can he make?