Unit 7 Contents

Solve the following problems. Be prepared to show or tell your strategy.

• Which problems can you solve in your head?
• Which problems can you solve by sketching a number line or making a few quick notes?
• Which problems do you need to use pencil and paper to solve?

1. 35 − 9
2. 987 − 47
3. 90 − 70
4. 100 − 25
5. 105 − 26
6. 100 − 68
7. 264 − 99
8. 140 − 60
9. 104 − 97

Solve the problems below in your head by sketching a number line or making a few quick notes.

1. 15 − 7
2. 46 − 10
3. 46 − 9
4. 80 − 30
5. 74 − 30
6. 74 − 32
7. 150 − 70
8. 80 − 24
9. 40 − 6
1. 100 − 49
2. 100 − 74
3. 107 − 49
4. 107 − 98
5. 345 − 99
6. 300 − 49
3. Explain how you solved Question 2B.
4. A blue whale is 110 feet long. How much longer is a blue whale than Sue?