Page 76 - ArithBook5thEd ~ BCC

Solution. Dividing 84 by 7 yields a quotient of 12 and a remainder of 0. Thus

84 0
=12 =12,
7 7
a whole number.
Here are some everyday uses of mixed numbers.
Example 80. Five hikers want to share seven chocolate bars fairly. How many bars does each hiker
get?

Solution. For fairness, each of the five hikers should get the same amount: exactly one fifth of the
chocolate. There are seven bars, so the amount (in chocolate bars)that each hiker should get is

7 2
=1 .
5 5
2
Each hiker gets 1 chocolate bars.
5
Example 81. Julissa waited 5 minutes for the train on Monday, 2 minutes on Tuesday, and then 4, 8,
and 3 minutes on Wednesday, Thursday, and Friday, respectively. What was her average wait time for
the week?

Solution. Recall that the average of a set of numbers is their sum, divided by the number of numbers.
In this case, we want the average of the five numbers {5, 2, 4, 8, 3},which is
5+ 2+ 4 + 8+ 3 22 2
= =4 .
5 5 5
2
Her average wait time was 4 minutes. (Extra credit: how long is two fifths of a minute, in seconds?)
5
3.3.2 Exercises
Convert the following improper fractions into mixed numbers:
19
1.
3
11
2.
2
135
3.
5
99
4.
98
77
5.
5
Use mixed numbers to answer the following questions:
6. Three boys share four sandwiches fairly. How many sandwiches does each boy get?

7. What is the average of the set of numbers {11, 14, 9, 12}?

8. During the first seven days of January, Bill travels 31, 37, 46, 31, 77, 50 and 40 miles respectively.
What is his average daily travel distance?

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