Unit 3 Review: Rates, Ratios, and Proportions

Front

What is a unit rate?

Back

A unit rate is a comparison of two different quantities when they are combined together. It expresses how much of one quantity corresponds to one unit of another quantity, often expressed as 'per' something.

Front

How do you calculate the unit rate?

Back

To calculate the unit rate, divide the total amount of one quantity by the total amount of the other quantity. For example, if you spend $40 on 5 pounds of concrete, the unit rate is $40 ÷ 5 = $8 per pound.

Front

What is a ratio?

Back

A ratio is a relationship between two numbers indicating how many times the first number contains the second. It can be expressed in various forms, such as fractions, decimals, or with a colon.

Front

How do you simplify a ratio?

Back

To simplify a ratio, divide both terms of the ratio by their greatest common divisor (GCD). For example, the ratio 20 to 25 can be simplified by dividing both by 5, resulting in 4 to 5.

Front

What is a proportion?

Back

A proportion is an equation that states that two ratios are equal. For example, if a/b = c/d, then a, b, c, and d are in proportion.

Front

How do you solve a proportion?

Back

To solve a proportion, cross-multiply the terms and set the products equal to each other. For example, if 1/3 = x/6, then 1 * 6 = 3 * x, leading to x = 2.

Front

What is the relationship between ratios and fractions?

Back

Ratios can be expressed as fractions. For example, the ratio 3 to 4 can be written as the fraction 3/4.

Front

How do you find the missing number in a ratio?

Back

To find the missing number in a ratio, set up a proportion and solve for the unknown. For example, if the ratio is 3:x = 6:12, then cross-multiply to find x.

Front

What is the unit rate of words typed per minute if Justin types 408 words in 4 minutes?

Back

To find the unit rate, divide the total words by the total minutes: 408 words ÷ 4 minutes = 102 words per minute.

Front

What does it mean to 'simplify' a ratio?

Back

To simplify a ratio means to reduce it to its simplest form, where the two numbers have no common factors other than 1.