Hands-on math!

Washington State Math Olympiad
Hints and Solutions
2007 Grade 5 Measurement
Problem
1) A doctor's prescription tells the pharmacist that Joey needs a teaspoon of medicine three times a day. A teaspoon is 5 milliliters. Joey needs to take the medicine for 10 days. How many milliliters of the medicine must the pharmacist put in the bottle for Joey's mom?
2) Trevor and Debby are designing a fort. They notice that if they increase the length of the floor by 2 feet then the floor area will increase by 12 square feet. If they increase the width by 3 feet then the floor area will increase by 24 square feet. What are the dimensions of the floor in their design?

Problem

3) In a regular octagon the lengths of the sides are all equal and the angles at the vertices are all equal. At a playground there is a merry-go-round for kids to spin around on that's in the shape of a regular octagon. The handles to hold on to go from the center of the merry-go-round out to each vertex. What is the angle created at the center between two adjacent handles?

4) A box has volume 24 cubic feet. It has a length of 3 feet and a width of 2 feet. If the width is increased by 1 foot, by how much does the volume increase?

5) Ella estimates the distance between two cities on a map using her thumb from knuckle to thumb tip. The distance is 7 thumbs units. Pete uses his thumb to measure the same distance and comes up with 6 thumb units. Her thumb unit measures 15 miles what does Pete's thumb unit measure?