6th Grade 12/5: Ratios, Proportions and Percents

Front

What is a ratio?

Back

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

Front

How do you express a ratio?

Back

Ratios can be expressed in three ways: as a fraction (1/2), with a colon (1:2), or in words (1 to 2).

Front

What is a proportion?

Back

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

Front

How do you solve a proportion?

Back

To solve a proportion, cross-multiply the terms and set the products equal to each other.

Front

What is a percent?

Back

A percent is a ratio that compares a number to 100, represented by the symbol %.

Front

How do you convert a fraction to a percent?

Back

To convert a fraction to a percent, divide the numerator by the denominator and multiply by 100.

Front

How do you find the percent of a quantity?

Back

To find the percent of a quantity, multiply the quantity by the percent (as a decimal).

Front

What is the formula for finding the percent increase?

Back

Percent Increase = (New Value - Original Value) / Original Value x 100.

Front

What is the formula for finding the percent decrease?

Back

Percent Decrease = (Original Value - New Value) / Original Value x 100.

Front

How do you find the total number of items from a ratio?

Back

To find the total number of items from a ratio, add the parts of the ratio together and then use the ratio to find the individual quantities.