Solving Proportions

Front

What is a proportion?

Back

A proportion is an equation that states that two ratios are equal.

Front

How do you set up a proportion to solve for an unknown?

Back

To set up a proportion, you can use the formula a/b = c/d, where a and b are known values, and c is the unknown value you want to find.

Front

What is the cross-multiplication method in solving proportions?

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 the ratio of dogs to cats is 5 to 3 and there are 25 dogs, how many cats are there?

Back

To find the number of cats, set up the proportion 5/3 = 25/c. Cross-multiply to find c = 15.

Front

How do you find the unit rate from a given ratio?

Back

To find the unit rate, divide both terms of the ratio by the second term.

Front

If Hunter buys 36 baseball cards for $18, what is the cost per card?

Back

The cost per card is $18/36 = $0.50 per card.

Front

How do you determine how many items can be bought with a different amount of money using proportions?

Back

Set up a proportion comparing the number of items to the amount of money spent, then solve for the unknown.

Front

What is the formula to find the total cost when given a unit price and quantity?

Back

Total cost = unit price × quantity.

Front

If Finley pays $53.75 for 5 hours, how much does he pay per hour?

Back

He pays $53.75/5 = $10.75 per hour.

Front

How do you solve for an unknown in a proportion when given a variable?

Back

Isolate the variable by cross-multiplying and then solving the resulting equation.