Lesson 6 Division as an Unknown Factor

- Let’s connect division equations to multiplication equations.

Warm-up Notice and Wonder: Missing Numbers

What do you notice? What do you wonder?

$3 \times ? = 12$

$12 \div 3 = ?$

Activity 1 Equations about Onions

A farmer puts 14 onions into 2 bags, with the same number of onions in each bag.

Lin says the situation should be represented by the equation:

$2 \times = 14$

Mai says the situation should be represented by the equation:

$14 \div 2 =$

Whose equation do you agree with? Be ready to explain your reasoning.

Activity 2 At the Farmers’ Market

Complete each row. Be prepared to explain your reasoning.

situation	multiplication equation	division equation
Elena’s family buys 18 avocados at the farmers market. The avocados are in bags of 3 each.		$18 \div 3 =$
Andre sees 25 tomatoes. They are in 5 bunches. Each bunch has the same number of tomatoes.	$5 \times ? = 25$	$25 \div 5 = ?$
Lin orders 6 banana fritters. The fritters are served on 2 plates and each plate has the same number of fritters.	$2 \times ? = 6$
	$\times 10 = 30$	$30 \div 10 =$

Practice Problem

Problem 1

There are 35 books on the bookcase. There are 7 books on each shelf. How many shelves are there? Explain how the equations $35 \div 7 = ?$ and $? \times 7 = 35$ both represent the situation.