Conversions & Proportions

Front

What is a proportion?

Back

A proportion is an equation that states that two ratios are equal. It can be used to solve problems involving scaling and comparisons.

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

If a 12-ounce shampoo bottle lasts 16 weeks, how do you find the duration for an 18-ounce bottle?

Back

Use the ratio of ounces to weeks: (12 oz / 16 weeks) = (18 oz / x weeks). Cross-multiply and solve for x.

Front

What is the unit rate?

Back

The unit rate is a comparison of two different quantities when they are combined together. It is often expressed as a quantity per one unit.

Front

How do you calculate the cost per item using proportions?

Back

To find the cost per item, divide the total cost by the number of items. For example, if 5 books cost $55.40, the cost per book is $55.40 / 5.

Front

What is the formula for finding the total cost using proportions?

Back

Total Cost = (Cost per item) x (Number of items). Use this formula to find the total cost for any quantity.

Front

How do you convert milligrams to milliliters using proportions?

Back

Set up a proportion based on the known values. For example, if 10 mg is in 2 mL, use the ratio to find how many mg are in 28 mL.

Front

What is the relationship between ingredients in a recipe?

Back

The relationship between ingredients in a recipe is based on proportions. If one ingredient is increased, others must be adjusted to maintain the same ratio.

Front

How do you adjust a recipe when changing the quantity of one ingredient?

Back

To adjust a recipe, maintain the same ratio by multiplying or dividing the other ingredients by the same factor used for the changed ingredient.

Front

If 3 pounds of hamburger meat costs $6, how do you find the cost for 10 pounds?

Back

Set up a proportion: (3 lbs / $6) = (10 lbs / x). Cross-multiply to find x, which is the total cost for 10 pounds.