Solving Proportions

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 then solve for the variable.

Front

If 10 cookies require 2.2 scoops of flour, how many scoops are needed for 15 cookies?

Back

3.3 scoops

Front

What does it mean for two quantities to vary directly?

Back

Two quantities vary directly if one quantity increases, the other also increases at a constant rate.

Front

If a car travels 280 miles in 7 hours, what is its speed?

Back

Speed = Distance / Time = 280 miles / 7 hours = 40 miles per hour.

Front

How do you find the time taken to travel a certain distance at a constant speed?

Back

Time = Distance / Speed.

Front

If x/4 = 7, what is the value of x?

Back

x = 28.

Front

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

Back

If a/b = c/d, then ad = bc.

Front

If a car travels 120 miles in 3 hours, how long will it take to travel 200 miles?

Back

5 hours.

Front

What is the relationship between distance, speed, and time?

Back

Distance = Speed × Time.