Extended Facts
Ballpark Estimates
Number Stories
What's my Rule?
Addition
100
5+7= 50+70= 500+700=
12 120 1,200
100
66 + 21
70 + 20 90
100
There were 23 3rd graders and 41 4th graders on the playground. How many children were on the playground altogether? Number Sentence: Answer:
Number Sentence: 23 + 41 = 64 Answer: 64 children
100
Rule: Add 12 In Out 4 10 45 56 72
Out 16 22 57 68 84
100
42 + 36
78
200
9+4= 90+40= 900+400=
13 130 1,300
200
49 - 13
50 - 10 40
200
Maria lives 32 blocks from school. Abraham lives 68 blocks from school. How much further is Abraham from school than Maria? Number Sentence: Answer:
Number Sentence: 68 - 32 = 36 Answer: 36 blocks
200
Rule: Subtract 50 In Out 150 200 70 100 50
Out 100 150 20 50 0
200
475 + 23
498
300
14-8= 140-80= 1,400-800=
6 60 600
300
352 + 359
350 OR 300 + 360 + 400 710 700
300
Amanda went to the store with $40. She bought a toy that cost $23. How much money does Amanda have left? Number Sentence: Answer:
Number Sentence: 40 - 23 = 17 Answer: $17 (dollars)
300
Rule: Add 8 In Out 14 24 44 74 94
In 22 32 52 82 102
300
39 + 57
96
400
16-3= 160-30= 1,600-300=
13 130 1,300
400
727 - 126
730 OR 700 - 130 - 100 600 600
400
The high temperature on November 1st was 45 degrees. On February 1st, the high temperature was 18 degrees. What is the difference between the two temperatures? Number Sentence: Answer:
Number Sentence: 45 - 18 = 27 Answer: 27 degrees
400
Rule: Add 4 In Out 5 13 21 35 58
In Out 9 17 17 31 62
400
591 + 233
824
500
19-8= 190-80= 1,900-800=
11 110 1,100
500
375 + 635
380 OR 400 + 640 + 600 1,020 1,000
500
Taylor read her book for 23 minutes on Monday, 38 minutes on Tuesday, and 50 minutes on Wednesday. How many minutes did she read in all? Number Sentence: Answer:
Number Sentence: 23 + 38 + 50 = 111 Answer: 111 minutes
500
Rule: ? In Out 25 10 55 10 65 80 36
Rule: Add 15 In Out 25 10 40 55 5 20 65 80 36 51
500
657 + 268
925