Rounding Word Problems

Rounding Word Problems
  • Page 1
 1.  
Estimate the total cost of 3 albums marked $7.40, $8.65, and $11.95. Round to the nearest dollar.
a.
$25
b.
$18
c.
$28
d.
$20


Solution:

$7.40 rounded to the nearest dollar is $7.

$8.65 rounded to the nearest dollar is $9.

$11.95 rounded to the nearest dollar is $12.

The total cost of the 3 albums 7 + 9 + 12 = $28
[Add the values.]

The cost of 3 albums is about $28.


Correct answer : (3)
 2.  
Roddick earned $12.35 for mowing a lawn and $24.75 for working at a restaurant in a single day. Estimate the amount he earned on that single day. Round to the nearest dollar.
a.
$32
b.
$30
c.
$45
d.
$37


Solution:

Amount Roddick earned for mowing a lawn is $12.35.

$12.35 rounded to the nearest dollar is $12.

Amount Roddick earned working at a restaurant is $24.75.

$24.75 rounded to the nearest dollar is $25.

The amount Roddick earned in a single day 12 + 25 = $37

Amount Roddick earned in a single day is about $37.


Correct answer : (4)
 3.  
Amanda bought 10 books for $28.45, 5 pens for $15.15, and 5 pencils for $6.75. Estimate the total amount that Amanda spent.
a.
$60
b.
$50
c.
$30
d.
$45


Solution:

Cost of 10 books is $28.45.

$28.45 rounded to the nearest dollar is $28.

Cost of 5 pens is $15.15.

$15.15 rounded to the nearest dollar is $15.

Cost of 5 pencils is $6.75.

$6.75 rounded to the nearest dollar is $7.

Cost of all the items 28 + 15 + 7 = $50
[Add the values.]

The total amount spent by Amanda in buying all the items is about $50.


Correct answer : (2)
 4.  
Roseberg works 20 hours per week at a gas station where he earns $8.75 per hour. He also works 15 hours per week as a pizza delivery boy and earns $5.75 per hour. Estimate the amount Roseberg earns in a week.
a.
$240
b.
$270
c.
$370
d.
$300


Solution:

$8.75 rounded to the nearest dollar is $9.

Amount earned by Roseberg working 20 hours in a gas station 20 × 9 = $180

$5.75 rounded to the nearest dollar is $6.

Amount earned by Roseberg working 15 hours as a pizza delivery boy 15 × 6 = $90

Total amount earned by Roseberg per week is about $180 + $90 = $270

Estimated amount Roseberg earned in a week is $270.


Correct answer : (2)
 5.  
The cost of a book is $6.25 and the cost of a bag is $35.80. Find the cost of 15 books and 3 bags. Round to the nearest dollar.
a.
$180
b.
$189
c.
$190
d.
$198


Solution:

The cost of a book is $6.25.

$6.25 rounded to the nearest dollar is $6.

Cost of 15 books 15 × 6 = $90

The cost of a bag is $35.80.

$35.80 rounded to the nearest dollar is $36.

Cost of 3 bags 3 × 36 = $108

Cost of 15 books and 3 bags 90 + 108 = $198

So, the cost of 15 books and 3 bags is about $198.


Correct answer : (4)
 6.  
Justin made three telephone calls, which cost him $6.78, $3.82, and $7.18. Estimate the total money spent.
a.
$11
b.
$18
c.
$16
d.
$13


Solution:

$6.78 $7
[Round to the nearest dollar.]

$3.82 $4
[Round to the nearest dollar.]

$7.18 $7
[Round to the nearest dollar.]

$7 + $4 + $7 = $18
[Add the rounded values.]

Justin spent about $18 for telephone calls.


Correct answer : (2)
 7.  
Kathy needs to pay $59.65 for a book. If she has only ten dollar bills, then estimate how much money she should give to the clerk.
a.
round up to $59.70
b.
round down to $59.50
c.
round up to $60.00
d.
round down to $50.00


Answer: (c)


Correct answer : (3)
 8.  
Which of the following represents 2.388 rounded to the nearest tenth?
a.
3
b.
2.4
c.
2.3
d.
2.310


Solution:

2.388
[Original Decimal.]

As 3 is in the tenths place, 2.388 rounds to 2.3 or 2.4

8 is the digit to the right of 3.

Since 8 > 5, 2.388 rounds to 2.4 than 2.3

To the nearest tenth, 2.388 rounds to 2.4


Correct answer : (2)
 9.  
Find the decimal that represents 0.7167 rounded to the nearest hundredth and then to the nearest tenth.
a.
0.8
b.
0.9
c.
0.7
d.
0.6


Solution:

0.7167
[Original Decimal.]

The digit in hundredths place is 1.

The digit to the right of 1 is 6, which is greater than 5.

Since the decimal in thousandths place is greater than 5, to the nearest hundredths 0.7167 rounds to 0.72

Since 7 is in the tenths place, 0.72 rounds to 0.7 or 0.8

2 is the digit to the right of 7.

Since 2 < 5, 0.72 is closer to 0.7 than 0.8


Correct answer : (3)
 10.  
Which of the following represents 298.3669 rounded to the nearest hundredth and then to the nearest tenth?
a.
298.4
b.
298.37
c.
298.3
d.
298.5


Solution:

298.3669
[Original Decimal.]

The digit in the hundredths place is 6.

The digit to the right of 6 is 6 and 6 > 5.

298.37
The decimal rounded to nearest hundredths'

3 is in the tenths place so 298.36 rounds to 298.3 or 298.4

6 is the digit to the right of 3.

Since 6 > 5, 298.36 is closer to 298.4 than 298.3


Correct answer : (1)

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