Solving Proportions Word Problems

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 two ratios and set the products equal to each other.

Front

What is the formula for finding a missing value in a proportion?

Back

If a/b = c/d, then ad = bc. You can find the missing value by rearranging this equation.

Front

If 12 ounces of shampoo lasts 16 weeks, how do you find out how long 18 ounces will last?

Back

Set up a proportion: 12/16 = 18/x, then cross-multiply and solve for x.

Front

If a car travels 420 miles in 8 hours, how do you find the distance it will travel in 12 hours?

Back

First, find the rate: 420 miles / 8 hours = 52.5 miles/hour. Then multiply the rate by 12 hours.

Front

What is the relationship between the number of students with an A and the total number of students in a class?

Back

The ratio of students with an A to the total number of students can be used to find how many students have an A in a larger group.

Front

If 14 sticks of pepperoni are needed for 28 pizzas, how do you find the amount needed for 36 pizzas?

Back

Set up a proportion: 14/28 = x/36, then cross-multiply and solve for x.

Front

How do you calculate the time it takes to travel a certain distance at a constant speed?

Back

Use the formula: time = distance / speed.

Front

What is the unit rate?

Back

The unit rate is a comparison of two different quantities when they are combined together, expressed as a quantity per one unit.

Front

How can you use proportions to solve real-world problems?

Back

Proportions can be used to compare ratios and find unknown values in various situations, such as cooking, travel, and classroom scenarios.