Percents and Proportions

Front

What is a percent?

Back

A percent is a ratio expressed as a fraction of 100. It represents a part of a whole.

Front

How do you convert a percent to a decimal?

Back

To convert a percent to a decimal, divide the percent by 100. For example, 15% = 0.15.

Front

What is a proportion?

Back

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

Tags

CCSS.7.RP.A.2A

Front

How do you set up a proportion to solve for an unknown?

Back

Cross-multiply the two ratios and set them equal to each other to solve for the unknown.

Tags

CCSS.7.RP.A.3

Front

What is the formula to find the percent of a number?

Back

The formula is: Percent = (Part/Whole) x 100.

Front

How do you find the whole when given a part and a percent?

Back

Use the formula: Whole = Part / (Percent/100).

Tags

CCSS.6.RP.A.3C

Front

What does it mean to find a percent of a number?

Back

Finding a percent of a number means calculating how much that percent represents in relation to the whole number.

Front

How do you calculate a discount on an item?

Back

To calculate a discount, multiply the original price by the discount percent (as a decimal) and subtract that from the original price.

Tags

CCSS.6.RP.A.3C

Front

What is the final cost after tax?

Back

Final cost = Original price + (Original price x Sales tax rate).

Tags

CCSS.6.RP.A.3C

Front

How do you maintain proportions in a recipe?

Back

To maintain proportions, scale all ingredients by the same factor based on the change in one ingredient.

Tags

CCSS.7.RP.A.2A