We included HMH Into Math Grade 2 Answer Key PDF Module 20 Lesson 1 Relate Inches to a Number Line to make students experts in learning maths.
HMH Into Math Grade 2 Module 20 Lesson 1 Answer Key Relate Inches to a Number Line
I Can solve two-digit addition and subtraction problems using an inch ruler or a yardstick as a number line.
Spark Your Learning
Use the ruler to solve the riddle. Show your work. On what number do you end?
I ended on ________.
Riya is solving a number riddle with an inch ruler. Show how Riya can solve the problem using a ruler: Start at 3. Add 3. Add H more. Subtract 2. Add 4. On what number do you end? This is the answer to the riddle.
Answer:
so, the number ends on 12
Add 3
3 + 3 = 6
add 4
6 + 4 = 10
subtract 2
10 – 2 = 8
add 4
8 + 4 = 12
Build Understanding
Miss Ines has a rope that is 35 inches long. She cuts off 14 inches from the rope. How long is the rope now?
A. How can you solve this problem using a measuring tool?
Answer:
On the measuring rope mark up to 35 then remove the length of 14 inches
B. Solve this problem using a measuring tool. Show your work on a number line.
The rope is _________ inches long now.
Answer:
The rope is 21 inches long now.
C. How are an inch ruler and a yardstick like a number line?
Answer:
Explanation:
Miss Ines has a rope that is 35 inches long.
She cuts off 14 inches from the rope.
let n be the unknown length of rope
n = 35 – 14
n = 21
21 inches is the rope now
Turn and Talk How can you use an inch ruler or a yardstick to make a number line?
Answer:
A ruler is a tool which helps people to measure, the length.
so, we can use a number line for measuring the length.
Step It Out
Question 1.
Mia has 22 markers. She gives 12 markers to her friend. How many markers does Mia have now?
A. On the yardstick, show the number of markers Mia has.
Answer:
B. How many markers does Mia give to her friend? Write the number as tens and ones.
________ markers = ________ ten _________ ones
Answer:
12 markers = 1 ten 2 ones
C. Count back by ones to subtract the ones. Show your work on the yardstick.
Answer:
D. Count back by ten to subtract the ten. Show your work on the yardstick.
Answer:
22 – 10 = 12
E. Complete the equation to show how many markers Mia has now.
________ markers – ___________ markers = __________ markers
Answer:
22 markers – 12 markers = 10 markers
Explanation:
Mia has 22 markers.
She gives 12 markers to her friend.
let n be the markers that Mia have.
n = 22 – 12
n = 10
10 markers that Mia have now
Check Understanding
Question 1.
What is the total length of 23 inches and 12 inches? Use the yardstick to solve. Show your work.
23 + 12 = __________ inches
Answer:
23 + 12 = 35 inches
Explanation:
let n be the length unknown
n = 23 + 12
n = 35
On Your Own
Question 2.
Use Repeated Reasoning Mr. Brown is baking muffins. He has 15 muffins. Then he bakes 15 more muffins. How many muffins does Mr. Brown have now?
________ + _______ = ________ muffins
Answer:
15 + 15 = 30 muffins
Explanation:
Mr. Brown is baking muffins. He has 15 muffins.
Then he bakes 15 more muffins.
let n be the unknown muffins
n = 15 + 15 = 30
30 muffins that Mr. Brown have now
Question 3.
Open-Ended Explain how you used the yardstick to solve Problem 2.
Answer:
15 + 15 = 30
Explanation:
On the yard stick marked number15 as the starting point and adding 15 to it.
so, moving forward on number line and counting numbers up to 15 to reach number 30.
Reason Use a yardstick to solve.
Question 4.
28 – 15 = ___________
Answer:
28 – 15 = 13
Explanation:
On the yard stick marked number 28 as the starting point and subtracting 15 to it.
so, moving backward on number line and counting numbers up to 15 to reach number 28.
Question 5.
________ = 17 + 14
Answer:
31 = 17 + 14
Explanation:
On the yard stick marked number 17 as the starting point and adding 14 to it.
so, moving forward on number line and counting numbers up to 14 reached 31
Question 6.
30 – 18 = ___________
Answer:
30 – 18 = 12
Explanation:
On the yard stick marked number 30 as the starting point and subtracting 18 to it.
so, moving backward on number line and counting numbers up to 18 to reach number 12
I’m in a Learning Mindset!
How did practice help me master using an inch ruler or a yardstick to add or subtract?
Answer:
marking the addends on the ruler and adding the numbers one by one
makes me understand the concept.