Vocabulary
You can ______________ by rounding numbers to find an answer that is close.
Estimate
1 more than 256
257
Round 43 to the nearest tens
40
66 + 34
100
A dog weighs 67 pounds. A horse weighs 1,612 pounds. How much do both weigh together?
1,679
These show you how to group numbers.
Parentheses
50 more than 222
272
Round 56 to the nearest tens
60
73 + 19
92
One cupcake has 113 sprinkles. How many sprinkles would 3 cupcakes have?
339
This property shows you that the answer to a number plus 0 is that number.
Identity property
100 more than 1,365
1,465
Round 316 to the nearest tens
320
888 + 37
925
19 second graders, 23 third graders, and 9 fourth graders enter a contest. Are at least 50 students in the contest?
This property shows you that when you add numbers, the order doesn't matter.
Commutative property
1,000 more than 1,010
2,010
Round 487 to the nearest hundreds
490
329 + 34
363
Ann earns 2,226 dollars from the bake sale. Kelly earns 1,330 from another bake sale. What is the total amount of money earned from the two sales?
3,556
(8 + 7) + 1
(1 + 7) + 8
Associative property
3,000 more than 3,740
6,740
Round 3,710 to the nearest hundreds
3,700
508 + 426
934
Jack plays video games for 2 hours Monday and 2 hours Tuesday. 2 hours is 120 minutes. He plays for the same amount on Wednesday. How many minutes total did he play?
360