Vocabulary
What does sum mean?
To add
235 + 429
664
864 - 428
436
Find the difference of 781 and 39
742
Round to the nearest hundreds
890
What does difference mean?
To subtract
894 +90 + 324
1,308
432-89
343
Find 78+456+108. Then subtract from 900
258
Round to the nearest ten and hundred
555
550
600
What does it mean to estimate?
To round
Find the sum of 146 and 243. Then add that sum to 349.
738
7,908-346
7,562
How many more is 870 than 67
803
Estimate to find the difference: (to the nearest ten)
671 and 842
170
What is a conjecture?
An educated guess based on facts given; a math argument
Which partial sum is correct for 567 + 345?
a. (500+300) + (67+40) + (7+5)
b. (500+300) + (60+40) + (7+5)
c. (500+300) + (60+40) + (5+5)
d. (500+500) + (60+40) + (7+5)
b. (500+300) + (60+40) + (7+5)
900-389
511
How many times do you need to regroup?
345-289
2 times
Check by adding. Show the problem and the sum.
721 - 399
322 + 399 = 721
What is the answer in a subtraction problem called?
The difference
Find the sum of 54 and 548. Then take that sum away from 892.
290
800 - 299
501
Is 650 + 23 greater than 680?
Prove your conjecture
650 + 23 = 673
No because 673 is less than 680
The baseball team is having a fundraiser. Their goal is to raise $850. They have made $439 of their goal so far. How much more do they need to raise in order to meet their goal?
$411