3-Digit Addition
310 + 159 =
469
500 - 100
400
11
Round 73 to the nearest ten.
70
John is writing a math equation to represent a word problem about the total number of markers in Mrs. Tran and Mrs. Laragy's class.
75 + 24 = m
Why do you think John used m in his equation?
Sometimes mathematicians use letters to represent the missing information in an equation. John used m to represent the total number of markers.
425 + 253 =
678
320 - 180 =
140
7 + ___ = 9 + 4
6
Round 73 to the nearest hundred.
100
Nancy and Jane were collecting shells at the beach this summer. Nancy collected 472 shells. Jane collect 427 shells. How many more shells did Nancy collect this summer?
Nancy collected 45 more shells than Jane.
418 + 256 =
674
427 - 283 =
144
11 - 5 = 4 + ___
2
Round 635 to the nearest hundred.
600
Nancy and Jane were collecting shells at the beach this summer. Nancy collected 472 shells. Jane collect 427 shells. How many more shells did Nancy collect this summer?
Choose ALL the equations that represent this problem.
A. 472 + 427 = s
B. 472 + s = 427
C. 472 - 427 = s
D. 427 + s = 472
E. 472 - s = 427
C. 472 - 427 = s
D. 427 + s = 472
E. 472 - s = 427
454 + 371 =
825
521 - 384 =
137
50 = 79 - ___
30 + ___ = 29 + 50
Round 635 to the nearest ten.
640
Jessie was making chocolate chip cookies. She had a bag with 458 chocolate chips to make the cookies. She used 273 chocolate chips. Then her mom gave her 74 more chocolate chips.
How many chocolate chips does she have now?
Jessie has 259 chocolate chips.
599 + 354 =
953
945 - 387 =
558
30 + ___ = 29 + 50
49
Round 572 to the nearest ten: ___
Round 572 to the nearest hundred: ___
570 and 600
Jessie was making chocolate chip cookies. She had a bag with 458 chocolate chips to make the cookies. She used 273 chocolate chips. Then her mom gave her 74 more chocolate chips.
How many chocolate chips does she have now?
Write an equation to represent this problem. Use c for chocolate chips.
(458 - 273) + 74 = c