Rounding
Write 4,306 in expanded form.
4 thousand + 300 + 6
Use the partial sums method to solve.
417 + 266 =
400 + 200 = 600
10 + 60 = 70
6 +7 =13
600 + 70 + 13 = 683
Decompose to subtract
548 - 214 =
548 - 214 =
500 - 200 = 300
40 - 10 = 30
8 - 4 = 4
300 + 30 + 4
Odd + Odd =
Even
At the apple orchard, the first grade class picked 274 apples and the second grade class picked 457 apples. One of the baskets tips over and spills and loses 182 apples. How many apples do the students still have?
549 Apples
Write 2,869 in expanded form. Label each place value
2,000 + 800 + 60 + 9
Thousands = 2
Hundreds = 8
Tens = 6
Ones = 9
Find the sum by estimating to the nearest tens.
452 + 248 =
452 -> 450
+ 248 -> 250
450 + 250 = 700
Write the related addition equation.
515 - 281 = ?
281 + ? = 515
Even + Odd =
Odd
The school is having a fundraiser this weekend. Their goal is to raise $800. On Saturday, they raised $372 and on Sunday they raised $296. How much money does the school still need to make to reach their goal?
132 Dollars
Round 853 to the nearest hundred.
900
Estimate to find the Sum by rounding to the nearest hundred.
326 + 556 =
326 -> 300
556 -> 600
300 + 600 = 900
Adjust and Solve.
612 - 216 =
512 - 216 =
612 -2 -> 610 610
216 -2 -> 214 - 214
_____________
Even + Even =
Even
Over the summer, the library checked out 578 books. During the month of August, they received 152 books back. In September, they received 254 books back. How many books are still checked out?
102 Books
Round 847to the nearest ten.
850
Adjust to solve
423
+ 257
__________
423 +3 -> 420
+ 257 -3 -> + 254
_______ _________
674
Decompose to Solve
425 - 126 =
425 - 126 = 299
What are the three addition properteis?
Commutative
Associative
Identity
The pumpkin patch picked 482 pumpkins last week and 204 so far this week. At the farm stand, they have sold 239 pumpkins so far. How many pumpkins do they have left?
447 Pumpkins
Round 675 to the nearest ten.
680
Use the partial sums method to solve.
241 + 328 =
241 + 328 =
200 + 300 = 500
40 + 20 = 60
1 + 8 = 9
500 + 60 + 9 = 569
Adjust to Solve
597 - 231 =
597 - 231 =
597 +3 -> 600
231 +3 -> - 234
__________
366
BONUS QUESTION!
Write an example of each of the three addition properties.
Examples...
Commutative
4 +3 = 3 + 4
Associative
(20+15) + 15 = 50
Identity
145 + 0 = 145
The most popular toy at the toy store this year is the building sets. Last week they received 428 building sets and this week they received 371 building sets. Their goal is to sell 900 building sets. How many more building sets do they need to reach their goal?
101 building sets