2-min Fluency Warm-up — Mental math.
45 − 10 =
63 + 10 =
300 + 100 =
500 − 100 =
Look at the ones first. Will you need to regroup? Write yes or no.
68 − 14: Regroup? ____
68 − 14 =
63 − 27: Regroup? ____
63 − 27 =
85 − 30: Regroup? ____
85 − 30 =
91 − 46: Regroup? ____
91 − 46 =
Think about what is happening. Draw a picture or write your thinking.
A farmer had 72 apples in his orchard. A storm knocked down some branches, and 28 apples fell to the ground and were lost. How many good apples does the farmer still have?
Draw or write your thinking:
apples
The school had 85 library books checked out. By Friday, 37 books had been returned. How many books are still checked out?
Draw or write your thinking:
books
One of these has a borrowing error. Find it, explain the error, and fix it.
53
- 17
44
✓ or ✗?
Explain the error:
Correct answer:
82
- 35
53
✓ or ✗?
Explain the error:
Correct answer:
Create Your Own
Make a subtraction problem that needs regrouping. Write it and solve it.
-
Strategy I used: