Devon works for a catering company. She is preparing the food for a party with 100 guests. Before she goes shopping for ingredients, she has to calculate how much food they will be making. She usually makes 375 milliliters of soup per person. How many liters of soup will Devon be making for the party?

In this concept, you will learn to identify equivalent metric units of capacity.

### Metric Units of Capacity

**Capacity** is the total amount of liquid an object can contain. Capacity is often measured using the metric units of **liter** (L) and **milliliter** (mL). Note that milliliter also uses the metric prefix of “milli-” to indicate that 1 milliliter is a thousandths of a liter. Look at the equivalent metric units of capacity.

\begin{align*}\begin{array}{rcl}
1 \ liter \ (L) & = & 1,000 \ milliliters \ (mL)\\
1 \ milliliter \ (mL) & = & 0.001 \ liter \ (L)
\end{array}\end{align*}

When converting from a larger unit to a smaller unit, multiply by 1,000.

When converting from a smaller unit to a larger unit, divide by 1,000.

Remember that multiplying by 1,000 is also the same as moving the decimal point 3 places to the right. Dividing by 1,000 is also the same as moving the decimal point 3 places to the left.

Here is a conversion problem.

Convert liters to milliliters. Liters are larger than milliliters, so multiply by 1,000.

4 liters is equivalent to 4,000 milliliters.

### Examples

#### Example 1

Earlier, you were given a problem about Devon at the catering company.

Devon needs to find out how many liters of soup she needs for 100 guests if each serving is 375 milliliters.

First, find the total amount of what she needs to make in milliliters. Multiply 350 mL by 100.

\begin{align*}350 \ mL \times 100 = 35,000 \ mL\end{align*}

Then, convert 35,000 milliliters to liters. A smaller unit is converting to a larger unit. Divide 35,000 mL by 1,000.

Devon will need to make 35 liters of soup.

#### Example 2

Find the equivalent unit.

Jamie is transferring a liquid from one container to another. She transfers 2.5 liters. How many milliliters did she transfer?

First, identify the unit conversion, 2.5 liters to milliliters. A larger unit is converting to a smaller unit.

Then, multiply by 1,000. You can also move the decimal point 3 places to the right.

Jamie transferred 2,500 milliliters of liquid.

**Find the equivalent units.**

#### Example 3

First, identify the unit conversion, 5 liters to milliliters. A larger unit is converting to a smaller unit.

Then, multiply by 1,000.

\begin{align*}5 \ L \times 1,000 = 5,000 \ mL\end{align*}

5 liters is equivalent to 5,000 milliliters.

#### Example 4

First, identify the unit conversion, 2,000 milliliters to liters. A smaller unit is converting to a larger unit.

Then, divide by 1,000.

2,000 milliliters is equivalent to 2 liters.

#### Example 5

First, identify the unit conversion, 2,000 milliliters to liters. A smaller unit is converting to a larger unit.

Then, divide by 1,000.

\begin{align*}4,500 \ mL \div 1,000 = 4.5 \ L\end{align*}

4,500 milliliters is equivalent to 4.5 liters.

### Review

Find the equivalent units.

- 4500 mL = _______ L
- 6900 mL = _______ L
- 4400 mL = _______ L
- 5200 mL = _______ L
- 1200 mL = _______ L
- 1800 mL = _______ L
- 2900 mL = _______ L
- 1300 mL = _______ L
- 2700 mL = _______ L
- 3 L = _______ mL
- 5.5 L = _______ mL
- 8 L = _______ mL
- 9.3 L = _______ mL
- 34.5 L = _______ mL
- 65.5 L = _______ mL

### Review (Answers)

To see the Review answers, open this PDF file and look for section 4.18.