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 two ratios and then solve for the unknown 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 and setting the two products equal to each other.

Front

If a:b = c:d, what is the relationship between a, b, c, and d?

Back

The relationship indicates that the ratio of a to b is equal to the ratio of c to d.

Front

How can you find a missing value in a proportion?

Back

You can find a missing value by setting up the proportion and using cross-multiplication to solve for the unknown.

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 of another quantity.

Front

How do you calculate a unit rate from a given scenario?

Back

To calculate a unit rate, divide the total quantity by the number of units.

Front

In the context of proportions, what does 'scaling up' mean?

Back

'Scaling up' means increasing both quantities in a proportion by the same factor to maintain the ratio.

Front

In the context of proportions, what does 'scaling down' mean?

Back

'Scaling down' means decreasing both quantities in a proportion by the same factor to maintain the ratio.

Front

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

Back

If a/b = c/x, then x = (b * c) / a.