Math Word Problems Demystified - A Self Teaching Guide

STRATEGY: Since you need to find a total and all items are in the same

units (inches), use addition.

IMPLEMENTATION: 1

1

4

þ

7

8

þ 2

3

16

¼ 1

4

16

þ

14

16

þ 2

3

16

¼ 3

21

16

¼ 4

5

16

EVALUATION: You can estimate the answer since 1^14 in. is about 1 in.,^78 in.

is about 1 in., and 2 163 in. is about 2 in. Hence, 1 in.þ1 in.þ2 in.¼4 in.

Since 4 in. is close to 4 165 in., your answer is probably correct.

EXAMPLE:How many pieces of ribbon 5^12 inches long can be cut from a

piece of ribbon 38^12 inches in length?

SOLUTION:

GOAL: You are being asked to find the number of pieces of ribbon that can

be cut from a piece 38^12 inches long.

STRATEGY: Since you are given a total (38^12 in.) and need to find how many

pieces (5^12 in.) are in the total, you can use division.

IMPLEMENTATION: 38

1

2

 5

1

2

¼

77

2



11

2

¼

777

21



21

111

¼ 7

Hence, you can cut 7 pieces.

EVALUATION: You can check by multiplying 7 512 ¼ (^3812)
EXAMPLE:A person has hiked 1^34 miles by noon. If his destination is 5^78
miles away from his starting point, how much further does he have to go?

SOLUTION:

GOAL: You are being asked to find how much further the person has to go.

STRATEGY: Since you need to find how much further, you use subtraction.

IMPLEMENTATION: 5

7

8

1

3

4

¼ 5

7

8

1

6

8

¼ 4

1

8

miles.

28 LESSON 4 Using Fractions