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 for x in a proportion?

Back

To solve for x in a proportion, cross-multiply the ratios and then isolate x.

Front

If 3 out of 5 teachers wore college shirts and 21 teachers wore college shirts, how do you find the total number of teachers?

Back

Set up the proportion: 3/5 = 21/x, then cross-multiply and solve for x.

Front

What is the formula to find the total when given a part and a ratio?

Back

Total = Part / (Ratio of Part) * (Total Ratio) or Total = Part / (Numerator of Ratio) * (Denominator of Ratio).

Front

If 3 eggs are needed for 24 muffins, how many eggs are needed for 144 muffins?

Back

Set up the proportion: 3/24 = x/144, then cross-multiply and solve for x.

Front

What does it mean for two ratios to be equivalent?

Back

Two ratios are equivalent if they represent the same relationship between quantities.

Front

How can you check if two ratios are equivalent?

Back

You can check by cross-multiplying the ratios and seeing if the products are equal.

Front

What is the first step in solving a word problem involving proportions?

Back

Identify the quantities involved and set up a proportion based on the relationships described.

Front

If x/12 = 3/4, what is the value of x?

Back

x = 12 * (3/4) = 9.

Front

In a proportion, if one ratio increases, what happens to the other ratio?

Back

If one ratio increases, the other ratio must also increase to maintain the equivalence.