Addition/Subtraction
385+283=668
What would the flip and check (inverse) problem look like?
668-283=385
Mia wants to collect 75 desk pets. She had 43, then she got 8 more for her birthday. How many cards does she still need to collect?
43+8=51 75-51=24
75-43=32 32-8=24
Solve using expanded form.
72+31
70+2 30+1
70+30=100
2+1=3
100+3=103
What is the missing number?
139+____=274
135
739-284=455
What would the flip and check (inverse) problem look like?
455+284=739
Cameron made 35 hamburgers and 24 hot dogs for his cookout. His guests ate 52 of them. How many hot dogs and hamburgers are leftover?
35+24=59
59-52=7 hotdogs and hamburgers
Solve using expanded form.
315+421
315=300+10+5
421=400+20+1
300+400=700
10+20=30
5+1=6
700+30+6=736
What is the missing number?
150+____=350
200
593+172=?
Bonus: How would you flip and check?
765
Bonus: 765-172=593
Sarah had $25. She bought 2 books for $7 each. How much money does she have left?
Bonus: Does she have enough money to buy more books?
7+7=14
25-14=$11
Bonus: Yes! She can buy another book for $7.
Solve using expanded form.
37+25+13
37=30+7
25=20+5
13=10+3
30+20+10=60
7+5+3=15
60+15=75
One eraser costs 5 cents. How much does it cost for 3 erasers?
Hint: Make a chart to help!
In Out
1 5 cents
2 10 cents
3 15 cents
683-256=?
Bonus: How would you flip and check?
427
Bonus: 427+256=683
Jonah is saving money for a new basketball. He needs $45. He got $20 for his birthday. He got $10 for his allowance. How much more does Jonah need?
25+10=35
45-35=10
Solve using expanded form.
498-221
498=400+90+8
221=200+20+1
400-200=200
90-20=70
8-1=7
Answer=277
Finish the table. Rule: +7
In Out
13 ___
28 ___
62 ___
Out
20
35
69
800-423=?
377
Dana has 14 Hershey bars. Dale has 13 cupcakes. Matt has 16 Snickers bars. How many candy bars do they have in all?
14+16=30 candy bars
Solve using expanded form.
454+386
454=400+50+4
386=300+80+6
400+300=700
50+80=130
4+6=10
700+130+10=840
What rule is this chart following?
In Out
28 22
84 78
39 33
Rule: -6