Ratios and Proportions Review

Front

What is a ratio?

Back

A ratio is a comparison of two quantities, showing how many times one value contains or is contained within the other.

Front

What is a proportion?

Back

A proportion is an equation that states that two ratios are equal.

Front

How do you calculate a percentage of a number?

Back

To calculate a percentage of a number, multiply the number by the percentage (in decimal form). For example, 19% of 221 is calculated as 221 * 0.19 = 41.99.

Front

How do you reduce a ratio?

Back

To reduce a ratio, divide both terms of the ratio by their greatest common divisor (GCD).

Front

What is the GCD of 48 and 12?

Back

The GCD of 48 and 12 is 12.

Front

Reduce the ratio 48:12.

Back

The reduced ratio is 4:1.

Front

What is the GCD of 80 and 225?

Back

The GCD of 80 and 225 is 5.

Front

Reduce the ratio 80:225.

Back

The reduced ratio is 16:45.

Front

If a class does 4 worksheets in 64 minutes, what is the rate of worksheets per minute?

Back

The rate is 4 worksheets / 64 minutes = 1 worksheet per 16 minutes.

Front

What rate would Darian need to work at to do the least amount of worksheets if the class does 4 worksheets in 64 minutes?

Back

Darian would need to work at a rate of 1:23.