We included HMH Into Math Grade 4 Answer Key PDF Module 2 Lesson 2 Subtract Whole Numbers and Assess Reasonableness to make students experts in learning maths.
HMH Into Math Grade 4 Module 2 Lesson 2 Answer Key Subtract Whole Numbers and Assess Reasonableness
I Can subtract whole numbers greater than 1,000 using place value and a grid with regrouping.
Spark Your Learning
Biologists classify living things on Earth by kingdoms. The approximate number of species in two different kingdoms are shown How many more fungi species are there than plant species?
Write the difference using only numbers.
Turn and Talk How did you know that you needed to regroup some of the place values?
Explanation:
Build Understanding
Question 1.
A natural history museum has 102,248 spider and scorpion specimens and 10,425 bird specimens. How many more spider and scorpion specimens are there than bird specimens?
Use the grid to help you solve the problem.
A. How can you use subtraction to solve this problem?
_____________________________
_____________________________
_____________________________
102,248 spider and scorpion specimens
and 10,425 bird specimens.
102,248 – 10,248= 92,000
B. Which place value should you start with when subtracting? _____________
Explanation:
When we do subtract we subtract from ones place
C. Subtract to find the answer.
Explanation:
D. Which place values did you regroup?
_________________________
Explanation:
we regrouped the thousands place
E. Use rounding to estimate the answer. Does your estimate show your answer is reasonable? Explain.
102,248 is rounded to 100,000
10,248 is rounded to 10,000
100,000 – 10000 = 90,000
My estimation is reasonable
as my exact answer is slightly vary to the exact answer.
Turn and Talk Does the estimated difference being close to your answer mean your answer is correct? Explain.
yes.
If the estimated difference is being close to our answer mean our answer is correct.
Step It Out
2. Of the 41,415 plant and animal species on a conservation group’s endangered species list, 16,306 are listed as near extinction. How many of the species on the list are not considered near extinction?
Explanation:
41,415 plant and animal species
16,306 are listed as near extinction
41,415 – 16,306 = 25,209
A. Estimate. Round to the nearest ten thousand. Then subtract. ____
41,415 – is rounded to 41,000
16,306 is round to 16000
41,000 – 16,000 = 25,000
B. Use the grid to record the problem.
C. Subtract the ones.
Explanation:
Continue to subtract by place value. What place values need to be regrouped?
Explanation:
We regrouped in ones place
There are ___ species considered endangered but not yet near extinction.
Explanation:
There are 25,000 species considered endangered but not yet near extinction.
D. Does your estimate show your answer is reasonable? Explain.
Explanation:
Yes, my answer is reasonable
as the estimation and exact answers are slightly varied.
Check Understanding Math Board
Question 1.
A scientific database lists 7,858 species of amphibians, and another database lists 5,513 species of mammals. How many more amphibian species than mammal species are listed?
There are ______ more amphibian species listed than mammal species.
Answer:
Explanation:
7,858 species of amphibians,
and another database lists 5,513 species of mammals.
7858 – 5513 = 2345
There are 2345 more amphibian species listed than mammal species.
Estimate. Then find the difference.
Question 2.
Estimate: ____
Answer:
Explanation:
518,112 is rounded to 500,000
295763 is rounded to 300,000
500,000 – 300,000 = 200,000
Question 3.
Estimate: ____
Answer:
Explanation:
560723 is rounded to 560,000
48911 is rounded to 50,000
560,000 – 50,000 = 510000
Question 4.
Estimate: ___
Answer:
Explanation:
5760 is rounded to 6000
2695 is rounded to 3000
6000 – 3000 = 3000
On Your Own
Question 5.
STEM At present, the highest peak of the Appalachian Mountains is 6,684 feet. Millions of years ago, before weathering and erosion had occurred, the highest peak was about 30,000 feet. What is the difference between the highest peak millions of years ago and the highest peak today? Explain how you know your answer is reasonable.
Answer:
the highest peak was about 30,000 feet.
the highest peak of the Appalachian Mountains is 6,684 feet
30,000 – 6,684 = 23,316
23,316 is the difference between the highest peak millions of years ago and the highest peak today
Question 6.
Use Structure Some biologists predict that there are about 27,500 species in the kingdom chromista and 36,400 species in the kingdom protozoa. How many more species of protozoa are predicted to exist than species of chromista? _____________
Answer:
27,500 species in the kingdom chromist
36,400 species in the kingdom protozoa
36,400 – 27,500 = 8,900
8,900 more species of protozoa are predicted to exist than species of chromist.
Estimate. Then find the difference.
Question 7.
Estimate: ______
Answer:
Explanation:
460,112 is rounded to 460,000
201,998 is rounded to 200,000
460,000 – 200,000 = 260,000
Question 8.
Estimate: ____
Answer:
Explanation:
8000 is rounded to 8000
2543 is rounded to 3000
8000 – 3000 = 5000
Question 9.
Estimate: ______
Answer:
Explanation:
88,741 is rounded to 88,000
16,304 is rounded to 16,000
88,000 – 16,000 = 72,000
Question 10.
Open Ended Write and solve a problem that requires finding the difference between 68,324 and 12,608.
_____________________________
_____________________________
Answer:
68,324
and 12,608.
I’m in a Learning Mindset!
How did subtracting greater numbers challenge me?
_____________________________
Explanation:
The regrouping makes the subtracting easier.