Addition Agents – Multi-digit addition problems
234 + 165 = ______
Focus: 3-digit addition, no regrouping
399
543 − 321 = ______
Focus: 3-digit subtraction, no regrouping
222
Liam has 245 baseball cards. His friend gives him 130 more cards.
How many baseball cards does Liam have now?
245 + 130 = 375
What word means the answer to an addition problem?
Sum
A notebook costs $3 and a pencil costs $2.
How much do they cost in all?
$3 + $2 = $5
468 + 297 = ______
Focus: Regrouping in the ones and tens places
765
804 − 267 = ______
Focus: Regrouping with zeros
537
A classroom library had 600 books. 185 books were checked out.
How many books are left in the library?
600 − 185 = 415
What word means the answer to a subtraction problem?
Difference
Liam walked 325 meters in the morning and 450 meters in the afternoon.
How far did he walk in total?
325 + 450 = 775 meters
1,354 + 2,786 = ______
Focus: Multi-digit addition with multiple regroupings
4140
2,305 − 1,478 = ______
Focus: Multiple regroupings
827
A baker made 1,275 muffins in the morning and 986 muffins in the afternoon.
She sold 1,450 muffins by the end of the day.
How many muffins were left?
1,275 + 986 = 2,261
2,261 − 1,450 = 811
What does it mean to regroup when solving an addition or subtraction problem?
To trade or move a value from one place value to another (for example, trading 10 ones for 1 ten).
A student had $20. She spent $7 on lunch.
How much money does she have left?
$20 − $7 = $13
3,409 + 5,678 + 212 = ______
Focus: Adding three numbers with regrouping
9299
6,000 − 3,586 = ______
Focus: Regrouping across zeros
2414
A school collected 3,458 cans of food in September and 2,769 cans in October.
They donated 4,125 cans to a food bank.
How many cans are still at the school?
3,458 + 2,769 = 6,227
6,227 − 4,125 = 2,102
Why is it helpful to estimate before solving a math problem?
To check if an answer is reasonable and to help predict about how large or small the answer should be.
A class read 1,245 pages on Monday and 1,368 pages on Tuesday.
On Wednesday, they read 1,100 pages.
How many pages did the class read in all?
1,245 + 1,368 = 2,613
2,613 + 1,100 = 3,713 pages
A library received 2,845 new books in September and 3,679 new books in October. In November, they received 1,486 more books.
How many new books did the library receive in all?
Focus: Real-world application + multi-step addition
8010
A school had 4,250 pencils. After giving some to students, 1,768 pencils remained.
How many pencils were given away?
4,250 − 1,768 = 2,482
A city park had 8,500 visitors over three days.
On Friday, 2,745 people visited. On Saturday, 3,189 people visited.
How many people visited the park on Sunday?
Explain how you know.
2,745 + 3,189 = 5,934
8,500 − 5,934 = 2,566
A student estimates 398 + 602 by rounding to 400 + 600.
What is the estimate, and why is this a good strategy?
The estimate is 1,000.
Rounding makes the numbers easier to add and helps check if the exact answer makes sense.
A bus traveled 2,450 miles during the school year.
By winter break, it had traveled 1,875 miles.
How many miles did the bus travel after winter break?
Explain how you know.
2,450 − 1,875 = 575 miles