Writing and 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 isolate the variable.

Front

What is the cross-multiplication method?

Back

The cross-multiplication method involves multiplying the numerator of one ratio by the denominator of the other ratio.

Front

If Alice earns $20.40 in 3 hours, how do you find her hourly rate?

Back

Divide the total earnings by the number of hours: $20.40 / 3 = $6.80 per hour.

Front

How do you find the total earnings for a different time period using a proportion?

Back

Set up a proportion using the known earnings and hours, then solve for the unknown.

Front

What is the formula for setting up a proportion?

Back

The formula is a/b = c/d, where a and b are the first ratio, and c and d are the second ratio.

Front

In the cake recipe, if 1.5 cups of milk is to 3 cups of flour, what is the ratio of milk to flour?

Back

The ratio of milk to flour is 1.5:3, which simplifies to 1:2.

Front

If Seth used 5 cups of flour instead of 3, how do you adjust the amount of milk?

Back

Set up a proportion: 1.5/3 = x/5, then solve for x.

Front

What is the value of k in the proportion 2/k = 4/8?

Back

Cross-multiply to find k: 2 * 8 = 4 * k, so k = 4.

Front

What does it mean if two ratios are equivalent?

Back

It means that they represent the same relationship or proportion between quantities.