Hands-on math!

Washington State Math Olympiad
Hints and Solutions
2010 Grade 6 Number Sense

Problem

1) A company creates parts for robots. 24% of the parts created are broken. If there are 42 broken parts, how many parts has the company made?

2) In the 6th grade class at Prime Middle School, the number of boys is 2/3 the number of girls. 1/4 of the girls wear glasses, and 1/8 of the girls who wear glasses have braces. If 3 girls have glasses and braces how many students are in the 6th grade class?

3) Complete the Magic Square. A Magic Square is a square array of numbers where the sum of the entries in each row, each column, and each diagonal are all the same. Express all four answers as fractions.

Problem

4) There are 25 children on a swim team. 10 swimmers are at most ten years old. 8 are older than twelve and 4 are older than thirteen. How many eleven and twelve year olds are on the team?

5) Liz was playing with a pile of pennies. She noticed when she stacked them in piles of three there was 1 left over. When she stacked them in piles of five there were 2 left over. There was more than one pile of 5. What is the smallest number of pennies she could have?