Number Patterns
Is 6+8 even or odd?
Even
Round 26 to the nearest 10.
30
13+42+37=
92
Use rounding to the nearest 10 to estimate the difference.
56-22=
56 -->
22 -->
40
Mike has 125 Lego pieces to build his Lego car. So far he has used 76 of them. How many pieces does he have left?
49 Lego pieces
Is 3+5+1= an even or odd number?
Odd the sum is 9.
Round 435 to the nearest 10
440
Write this number in expanded form (break apart strategy) and round to the nearest 10.
472 -->
Hundreds Ten Ones
_____ ______ _____
400+70+2
Rounded: 470
Hundreds Tens Ones
400 7 0
Use a number line to solve. Use a number bond to break apart 26.
64-26=
38
Sam used 56+37=93 to check her subtraction. Which math problem could she be checking? Write the answer(s) that are correct.
A. 56-37= __
B. 93-56= __
C. 93+37= __
D. 93-37= __
B and D
Complete the addition sentence to show the Commutative Property of Addition.
3+__ =__ 4+__=__
3+4 =7 4+3=7
Round 832 to the nearest 100.
800
100+40+3
+
200+30+5
__________ =
378
Estimate to the nearest hundred. Then find the difference.
345-132=
345 -->
132 -->
345 --> 300
132 --> 100
300-100=200
Fairmont Elementary School is having their yearly Read-a-thon. The third graders have read 482 books so far. Their goal is to read more than 800 books. What is the least number of books they need to read to reach their goal?
318 books because 800-482=318. Their goal is 800 books and they are at 482 so if they read 318 more, they will meet their goal.
Which equation shows the Commutative Property of Addition.
A. 12+6=18
B. 12+6=6+12
C. 6+(10+2)=(10+2)+6
B. 12+6=6+12
Estimate the sums. Round to the nearest hundred.
721+258=
721 -->
258 -->
1,000
458+336=
794
642-326=
316
Chris solves this problem. He says the difference is 214. Explain the mistake that Chris made. What is the correct difference.
452-258=
194
Is this equation 1+(4+5) = __ 5+(1+4)= __
A. Commutative Property of Addition
B. Identity Property of Addition
C. Associative Property of Addition
Associative Property of Addition
Estimate the difference. Round to the nearest hundred.
576-132=
576 -->
132 -->
500
257+125+531=
913
765-487=
278
There are 624 fiction books in the school library. The number of nonfiction books is 32 less than the number the fiction books.
Part A. ABOUT how many nonfiction books are there in the school library? Think round the numbers to the nearest 10.
Part B. How many fiction and nonfiction books are there in the school library altogether?
Part A. 624 --> 630
32 --> 30
630-30=600
Part B. 624-32=594