Page 242 - Basic College Mathematics with Early Integers

S E C T I O N 3.4 I ADDING AND SUBTRACTING LIKE FRACTIONS, LEAST COMMON DENOMINATOR 219

Review

Simplify. See Section 1.9.

83. 3 2 84. 4 3 85. 3 4

86. 7 2 87. 2 3 # 3 88. 4 2 # 5

Concept Extensions

Find and correct the error. See the first Concept Check in this section.

2 9 11 3 1 2 1
89. ± = 90. – = =
7 7 14 4 4 8 4

Solve.

91. In your own words, explain how to add like 92. In your own words, explain how to subtract like
fractions. fractions.

3
93. Use the map of the world for Exercises 51 through 94. Mike Cannon jogged of a mile from home and then
8
54 and find the sum of all the continents’ fractions.
rested.Then he continued jogging farther from home
Explain your answer.
3
for another of a mile until he discovered his watch
8
had fallen off. He walked back along the same path
4
for of a mile until he found his watch. Find how far
8
he was from his home.

Write each fraction as an equivalent fraction with the indicated denominator.

37 108
95. = 96. =
165 3630 215 4085

97. In your own words, explain how to find the LCD 98. In your own words, explain how to write a fraction as
of two fractions. an equivalent fraction with a given denominator.

Solve. See the second through fourth Concept Checks in this section.

2 7
99. Which of the following are equivalent to ? 100. True or false? When the fraction is rewritten
3 12
11
with a denominator of 48, the result is . If false,
10 40
a. b. 48
15 60 give the correct fraction.
16 200
c. d.
20 300