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Cogito

Grade 1 Math · Chapter 8 · Lesson 7

Practice Worksheet

Word Problems Within 40

Find the missing part as well as the whole.

10 problems · about 14 minutes · 1.OA.A.1

NameDate

Figure — use these to answer the problems

Set both parts. Watch the whole bar underneath change.
On the top shelf and On the bottom shelf
Books in all
Top shelf20
Bottom shelf10
Figure 1

Warm-Up Review

From earlier lessons. Loosen up before the new work.

3 problems

  1. From “Tape Diagrams for Stories”

    Parts of 13 and 12. What is the whole?

    Answer

  2. From “Making the Next Ten”

    29 + 5 = ?

    Answer

  3. From “Adding Ones Without Making a New Ten”

    31 + 6 = ?

    Answer

Warm Up

Straightforward practice. Get the method working first.

3 problems

  1. Whole 35, one part 15. Other part?

    Answer

  2. You know both parts. What do you do?

    • Put them together.
    • Take one away.

  3. Whole 30, one part 10. Other part?

    Answer

Build It Up

The same ideas with more to keep track of.

1 problem

  1. Parts 16 and 13. What is the whole?

    Answer

Stretch Yourself

Mixed problems. Work out what kind of question it is before you start.

3 problems

  1. Whole 28, one part 8. Other part?

    Answer

  2. At the Library

    25 books in all. 15 are red. How many are not red?

    Red and Not red
    In all
    Red15
    Not red10
    Answerbooks

  3. On the Bus

    14 children get on. Then 12 more. How many in all?

    Answerchildren