We included **H****MH Into Math Grade 1 Answer Key**** PDF** **Module 6 Lesson 5 Represent Addend Unknown and Both Addends Unknown Problems with a Visual Model** to make students experts in learning maths.

## HMH Into Math Grade 1 Module 6 Lesson 5 Answer Key Represent Addend Unknown and Both Addends Unknown Problems with a Visual Model

I Can make a visual model to solve word problems when one or both addends are unknown.

**Spark Your Learning**

Joey has 11 toy cars and buses. How many of each could he have?

Answer:

Explanation:

Joey has 11 toy cars and buses

The two combinations of 11 are

6 + 5 = 11 and 9 + 2 = 11

They could have 6 cars and 5 buses or 9 cars and 2 buses.

Explain that children should toss a number cube to determine the number of cars Joey has and then use strategies to find the number of buses. Children repeat the activity to find a different combination of cars and buses that make a total of 11.

**Build Understanding**

There are 12 trees. 8 trees are apple trees and the rest are pear trees. How many pear trees are there?

A. The bar model shows the problem. How can you make a concrete model to match the bar model?

B. Use the bar model to help you write an equation that solves the problem.

Equation: ______

C. There are ____ pear trees.

Answer:

The equation that solves the problem is

8 + 4 = 12

There are 4 pear trees.

**Turn and Talk** How would the bar model change if there were 7 apple trees instead of 8 apple trees?

**Step It Out**

1. There are 14 pens and pencils. 8 are pens. How many are pencils?

A. Use . Make a concrete model to match the bar model. Color to show what you did. Write the unknown addend.

B. Write a subtraction equation to match the problem.

Equation: ____

C. Write a subtraction equation to solve the problem.

Equation: ____

There are ___ pencils.

Answer:

Explanation:

There are 14 pens and pencils

8 are pens

The subtraction equation that helps to solve the problem is

14 – 8 = 6

There are 6 pencils.

**Turn and Talk** How does the bar model help you understand the problem? Explain.

**Step It Out**

2. Bella sees 15 horses. All are brown or black. How many could be black and how many could be brown?

A. Show the problem. Use if you need to.

____ brown horses and ____ black horses

B. Complete the bar model. Then write an equation to prove your answer ¡s correct.

Equation: _____

Answer:

Explanation:

Bella sees 15 horses

All are brown or black

The subtraction equation that helps to solve the problem is

15 – 10 = 5

The addition equation that matches with the problem is

10 + 5 = 15

There are 10 brown horses and 5 black horses.

**Check Understanding Math**** Board**

**Use a bar model to solve.**

Question 1.

Sam sees 13 cars. 7 are red and the rest are black. How many cars are black?

Equation: _________ ____ black cars

Answer:

Explanation:

Sam sees 13 cars

7 are red cars and the rest are black

The subtraction equation that helps to solve the problem is

13 – 7 = 6

The addition equation that matches with the problem is

7 + 6 = 13

There are 6 black cars.

**On Your Own**

**Use a bar model to solve.**

Question 2.

**Open Ended** Josephine has 12 flowers. Some are yellow and some are red. How many yellow and red flowers could there be?

Equation: _________

___ yellow flowers ___ red flowers

Answer:

Explanation:

Josephine has 12 flowers

Some are yellow and some are red

A combination of 12 is 7 and 5

7 + 5 = 12

Josephine has 7 yellow flowers and 5 red flowers.

Question 3.

**Reason** Harry has 14 toy airplanes. 9 are white and the rest are blue. How many airplanes are blue?

Equation: ____

___ blue airplanes

- Explain your thinking. _______

Answer:

Explanation:

Harry has 14 toy airplanes

9 are white and the rest are blue

The subtraction equation that helps to solve the problem is

14 – 9 = 5

The addition equation that matches with the problem is

9 + 5 = 14

There are 5 blue airplanes.

**On Your Own**

**Use a bar model to solve.**

Question 4.

Carlo sees 13 ducks. 8 are in the pond and the rest are in the grass. How many ducks are in the grass?

Equation: ______ ____ducks

Answer:

Explanation:

Carlo sees 13 ducks

8 are in the pond and the rest are in the grass

The subtraction equation that helps to solve the problem is

13 – 8 = 5

The addition equation that matches with the problem is

8 + 5 = 13 ducks.

**Complete the bar model. Write an equation to match.**

Question 5.

Equation: ______

Answer:

Explanation:

The subtraction equation that helps to solve the problem is

16 – 7 = 16

The addition equation that matches with the problem is

7 + 9 = 16

The sum of 7 and 9 is 16.

Question 6.

Equation: ______

Answer:

Explanation:

The subtraction equation that helps to solve the problem is

15 – 7 = 8

The addition equation that matches with the problem is

8 + 7 = 15

The sum of 8 and 7 is 15.

**I’m in a Learning Mindset!**

How does using a bar model help me understand solving problems with unknown addends?