Lesson 18 Represent Situations with Multiplication and Division

- Let’s represent problems with multiplication and division equations.

Warm-up Number Talk: Three and a Tenth

Find the value of each expression mentally.

$3 \times \frac{1}{10}$
$\frac{1}{10} \times 3$
$\frac{1}{10} \div 3$
$3 \div \frac{1}{10}$

Activity 1 Putting It All Together: Multiplication and Division

Problem 1

Diego’s dad is making hamburgers for the picnic. There are 2 pounds of beef in the package. Each burger uses $\frac{1}{4}$ pound. How many burgers can be made with the beef in the package?

Draw a diagram to represent the situation.
Write a division equation to represent the situation.
Write a multiplication equation to represent the situation.

Problem 2

Diego and Clare are going to equally share $\frac{1}{4}$ pound of potato salad. How many pounds of potato salad will each person get?

Draw a diagram to represent the situation.
Write a division equation to represent the situation.
Write a multiplication equation to represent the situation.

Activity 2 Multiplication or Division?

For your set of problems:

Write a multiplication or division expression for each situation.
Answer the question and write an equation. Make sure to include appropriate units. Draw a diagram, if needed.
Trade papers with your partner, and check your partner’s equations. If you disagree, work to reach an agreement.

Problem 1

Partner A:

The distance from Han’s house to Priya’s house is $\frac{4}{5}$ kilometer. Han has walked $\frac{3}{4}$ of the way already. How many kilometers has he walked?
Clare’s science class will test water samples in class. If there is a total of $\frac{1}{2}$ gallon of water and 10 groups, how much water will each group get if they split the water equally?
A container with 3 kilograms of strawberries is $\frac{1}{5}$ full. How many kilograms can the container hold?

Problem 2

Partner B:

It takes Han 4 minutes to walk $\frac{1}{3}$ kilometer. How many minutes will it take him to walk 1 kilometer?
Clare’s goal was to collect 4 kilograms of soil sample for her science project. She collected $2 \frac{2}{3}$ times her goal. How many kilograms of soil did Clare collect?
A container that can hold a $\frac{1}{2}$ pound of strawberries is $\frac{3}{5}$ full. How many pounds of strawberries are in the container?

Practice Problem

Problem 1

Clare has 5 yards of ribbon. It takes $\frac{1}{2}$ yard to make a bow. How many bows can Clare make with the ribbon? Write a multiplication and a division equation showing the solution.