We included HMH Into Math Grade 2 Answer Key PDF Module 20 Lesson 2 Add and Subtract Lengths in Inches to make students experts in learning maths.
HMH Into Math Grade 2 Module 20 Lesson 2 Answer Key Add and Subtract Lengths in Inches
I Can use a number line to represent and solve addition and subtraction problems about length in inches.
Spark Your Learning
How long is Sophie’s chain? How long is Anshu’s chain?
Sophie’s chain: ________ inches
Anshu’s chain: ________ inches
Sophie and Anshu use some 1-inch paper clips to make paper clip chains. When the children connected their chains, the combined chain measures 35 inches. How long could each child’s chain be? Represent the problem and write your answers.
Answer:
let us assume Sophie’s chain as 17 inches
And Anshu’s chain as 18 inches
17 + 18 = 35
Sophie’s chain: 17 inches
Anshu’s chain: 18 inches
Build Understanding
Question 1.
Damian places two boxes next to each other. One box is 13 inches long. The other box is 8 inches long. How long are the boxes together?
A. Write an equation to model this problem. Use a 
for the unknown number.
Answer:
= 13 + 8
B. How can you show the two lengths on the number line?
Answer:
C. The boxes are __________ inches long.
Answer:
The boxes are 21 inches long.
One box is 13 inches long.
The other box is 8 inches long.
let the unknown length be
= 13 + 8
= 21
Question 2.
Lana has a string that ¡s 24 inches long. She measures and cuts 9 inches from the string. How long ¡s the string now?
A. Write an equation.
Answer:
n = 24 – 9
B. Show the problem on the number line.
Answer:
C. Solve. The string is now _________ inches long.
Answer:
The string is now 15 inches long.
Explanation:
Lana has a string that ¡s 24 inches long.
She measures and cuts 9 inches from the string.
let n be the unknown length of the string
n = 24 – 9
n = 15
15 inches ¡s the string now.
Turn and Talk How does your visual model represent the second problem?
Answer:
Visual model helps easy subtraction and easy addition.
Step It Out
Question 1.
Mrs. Linn makes a bead necklace that is 23 inches long. She removes 7 inches of beads. How long is the necklace now?
A. Write an equation for the problem. Use represent the unknown number.
Answer:
= 23 – 7
B. Draw a line above the number line to show the length of the necklace at the start.
Answer:
C. Draw a second line to show the beads taken off the necklace.
Answer:
D. Solve. The necklace is _________ inches long now.
Answer:
The necklace is 16 inches long now.
Explanation:
Mrs. Linn makes a bead necklace that is 23 inches long.
She removes 7 inches of beads.
let be the unknown length
= 23 – 7
= 16
16 inches long is the necklace now
Check Understanding
Question 1.
Figaro has two pieces of string. Each one ¡s 8 inches long. How many inches of string does he have altogether? Write an equation using for the unknown number. Use the number line to solve.
___________ __________ inches of string
Answer:
8, 8 inches of string
Explanation:
let for the unknown number
Figaro has two pieces of string.
one string is 8 inches
= 8 + 8
= 16
On Your Own
Write an equation using for the unknown number. Use the number line to solve.
Question 2.
Use Structure Catalina has a ribbon that is 25 inches long. She cuts the ribbon into two pieces. One piece is 13 inches long. How long is the other piece?
The other piece of ribbon is _________ inches long.
Answer:
The other piece of ribbon is 12 inches long.
Explanation:
Catalina has a ribbon that is 25 inches long.
She cuts the ribbon into two pieces.
One piece is 13 inches long.
let be the other piece length
= 25 – 13
12 inches long is the other piece
Question 3.
Open-Ended Jorge’s beaded necklace is 13 inches long. Choose a number from 7 to 12 to represent the number of inches he adds to the necklace. Write an equation to show the new length. Show your work.
Answer:
Explanation:
Jorge’s beaded necklace is 13 inches long
Jorge’s added 10 more to the necklace
be the unknown length
= 13 + 10
= 23
The length of the necklace is 23 inches long.
I’m in a Learning Mindset!
What helps me stay focused on my work?
Answer:
The pointing on the number line,
adding and subtracting one number by one number helps me in focusing.