Mathematics » Properties of Real Numbers » Systems of Measurement

# Using Mixed Units of Measurement in the U.S. System

## Using Mixed Units of Measurement in the U.S. System

Performing arithmetic operations on measurements with mixed units of measures requires care. Be sure to add or subtract like units.

## Example

Charlie bought three steaks for a barbecue. Their weights were $$14$$ ounces, $$1$$ pound $$2$$ ounces, and $$1$$ pound $$6$$ ounces. How many total pounds of steak did he buy?

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### Solution

We will add the weights of the steaks to find the total weight of the steaks.

 Add the ounces. Then add the pounds. Convert 22 ounces to pounds and ounces. Add the pounds. 2 pounds + 1 pound, 6 ounces 3 pounds, 6 ounces Charlie bought 3 pounds 6 ounces of steak.

## Example

Anthony bought four planks of wood that were each $$6$$ feet $$4$$ inches long. If the four planks are placed end-to-end, what is the total length of the wood?

### Solution

We will multiply the length of one plank by $$4$$ to find the total length.

 Multiply the inches and then the feet. Convert 16 inches to feet. 24 feet + 1 foot 4 inches Add the feet. 25 feet 4 inches Anthony bought 25 feet 4 inches of wood.