Using a Third Thing

Compare two things that cannot be moved.

10 problems · about 11 minutes · 1.MD.A.1

NameDate

Figure — use these to answer the problems

The string sits between them. Compare each thing to the string.

Door

String

Table

Door9

String6

Table4

Figure 1

From earlier lessons. Loosen up before the new work.

7 problems

1
From “Longer Than, Shorter Than”
Why must you line up one end before comparing?
- Otherwise you cannot tell which is longer.
- To make it look neat.
2
From “True or False to Twenty”
Is 13 − 9 = 2 + 2 true?
- True. Both are 4.
- False.
From “Missing Numbers to Twenty”
8 + ? = 12
Answer
From “Take From Ten in Stories”
11 − 8 = ?
Answer
From “Taking From Ten”
13 − 9 = ?
Answer
From “Counting On or Making Ten?”
8 + 2 = ?
Answer
From “Start With the Bigger One”
6 + 9 = ?
Answer

Straightforward practice. Get the method working first.

2 problems

8
A rope is shorter than a string. The string is shorter than a pole. Is the rope shorter than the pole?
- Yes.
- No.
9
Why use a string instead of moving the door?
- Because the door cannot be moved.
- Because string is faster.

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

1 problem

10
The Bookcase
A shelf is longer than a string. The string is longer than a book. Is the shelf longer than the book?
- Yes, the shelf is longer.
- You cannot tell.