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 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 lasts 16 weeks, how long will 18 ounces last?

Back

24 weeks.

Front

What is a ratio?

Back

A ratio is a comparison of two quantities, showing the relative sizes of two or more values.

Front

How do you find the total number of items in a ratio?

Back

Add the parts of the ratio together to find the total.

Front

In a ratio of boys to girls of 4 to 5, how many girls are there if there are 12 boys?

Back

15 girls.

Front

What is the relationship between ratios and fractions?

Back

Ratios can be expressed as fractions, where the first quantity is the numerator and the second is the denominator.

Front

If a recipe calls for 1.5 cups of milk for every 3 cups of flour, how much milk is needed for 5 cups of flour?

Back

2.5 cups of milk.

Front

What is the concept of scaling in proportions?

Back

Scaling involves multiplying or dividing both terms of a ratio by the same number to maintain the proportion.