Ratios Study Guide

Front

What is a ratio?

Back

A ratio is a comparison of two quantities that shows the relative size of one quantity to another, often expressed as 'a to b' or a:b.

Front

How do you find the total number of coins in a piggy bank?

Back

To find the total number of coins, add the number of each type of coin together.

Front

If Ms. Graves has 3 pennies and 9 dimes, what is the total number of coins?

Back

Total coins = 3 (pennies) + 9 (dimes) = 12 coins.

Front

What is the ratio of dimes to total coins if there are 9 dimes and 12 total coins?

Back

The ratio of dimes to total coins is 9:12.

Front

How do you calculate the number of people with a bicycle based on a survey?

Back

Use the ratio of people with bicycles from the survey and apply it to the total population using cross-multiplication.

Front

If 5 out of 20 people have a bicycle, what is the ratio of people with bicycles?

Back

The ratio is 5:20, which simplifies to 1:4.

Front

What is the equivalent ratio of 3 free throws out of 7 attempts?

Back

The equivalent ratio can be expressed as 3:7.

Front

How do you determine if two ratios are equivalent?

Back

Two ratios are equivalent if they can be simplified to the same fraction or if their cross-products are equal.

Front

If Larry made 3 out of 7 free throws and Karl made 9 out of 14, are these ratios equivalent?

Back

No, because 3 times 3 equals 9, but 7 times 2 equals 14; therefore both parts were not multiplied by the same number.

Front

What is the cost per ounce if 30 oz costs $4?

Back

Cost per ounce = $4 / 30 oz = $0.1333 per oz.