1.2E: Exercises
- Page ID
- 30092
Practice Makes Perfect
Use Place Value with Whole Numbers
In the following exercises, find the place value of each digit in the given numbers.
51,493
- 1
- 4
- 9
- 5
- 3
- Answer
-
- thousands
- hundreds
- tens
- ten thousands
- ones
87,210
- 2
- 8
- 0
- 7
- 1
164,285
- 5
- 6
- 1
- 8
- 2
- Answer
-
- ones
- ten thousands
- hundred thousands
- tens
- hundreds
395,076
- 5
- 3
- 7
- 0
- 9
93,285,170
- 9
- 8
- 7
- 5
- 3
- Answer
-
- ten millions
- ten thousands
- tens
- thousands
- millions
36,084,215
- 8
- 6
- 5
- 4
- 3
7,284,915,860,132
- 7
- 4
- 5
- 3
- 0
- Answer
-
- trillions
- billions
- millions
- tens
- thousands
2,850,361,159,433
- 9
- 8
- 6
- 4
- 2
In the following exercises, name each number using words.
1,078
- Answer
-
one thousand, seventy-eight
5,902
364,510
- Answer
-
three hundred sixty-four thousand, five hundred ten
146,023
5,846,103
- Answer
-
five million, eight hundred forty-six thousand, one hundred three
1,458,398
37,889,005
- Answer
-
thirty-seven million, eight hundred eighty-nine thousand, five
62,008,465
In the following exercises, write each number as a whole number using digits.
four hundred twelve
- Answer
-
412
two hundred fifty-three
thirty-five thousand, nine hundred seventy-five
- Answer
-
35,975
sixty-one thousand, four hundred fifteen
eleven million, forty-four thousand, one hundred sixty-seven
- Answer
-
11,044,167
eighteen million, one hundred two thousand, seven hundred eighty-three
three billion, two hundred twenty-six million, five hundred twelve thousand, seventeen
- Answer
-
3,226,512,017
eleven billion, four hundred seventy-one million, thirty-six thousand, one hundred six
In the following, round to the indicated place value.
Round to the nearest ten.
- 386
- 2,931
- Answer
-
- 390
- 2,930
Round to the nearest ten.
- 792
- 5,647
Round to the nearest hundred.
- 13,748
- 391,794
- Answer
-
- 13,700
- 391,800
Round to the nearest hundred.
- 28,166
- 481,628
Round to the nearest ten.
- 1,492
- 1,497
- Answer
-
- 1,490
- 1,500
Round to the nearest ten.
- 2,791
- 2,795
Round to the nearest hundred.
- 63,994
- 63,940
- Answer
-
- 64,000
- 63,900
Round to the nearest hundred.
- 49,584
- 49,548
In the following exercises, round each number to the nearest ⓐ hundred, ⓑ thousand, ⓒ ten thousand.
392,546
- Answer
-
- 392,500
- 393,000
- 390,000
619,348
2,586,991
- Answer
-
- 2,587,000
- 2,587,000
- 2,590,000
4,287,965
Identify Multiples and Factors
In the following exercises, use the divisibility tests to determine whether each number is divisible by 2, 3, 5, 6, and 10.
84
- Answer
-
divisible by 2, 3, and 6
9,696
75
- Answer
-
divisible by 3 and 5
78
900
- Answer
-
divisible by 2, 3, 5, 6, and 10
800
986
- Answer
-
divisible by 2
942
350
- Answer
-
divisible by 2, 5, and 10
550
22,335
- Answer
-
divisible by 3 and 5
39,075
Find Prime Factorizations and Least Common Multiples
In the following exercises, find the prime factorization.
86
- Answer
-
\(2\cdot 43\)
78
132
- Answer
-
\(2\cdot 2\cdot 3\cdot 11\)
455
693
- Answer
-
\(3\cdot 3\cdot 7\cdot 11\)
400
432
- Answer
-
\(2\cdot 2\cdot 2\cdot 2\cdot 3\cdot 3\cdot 3\)
627
2,160
- Answer
-
\(2\cdot 2\cdot 2\cdot 2\cdot 3\cdot 3\cdot 3\cdot 5\)
2,520
In the following exercises, find the least common multiple of the each pair of numbers using the multiples method.
8, 12
- Answer
-
24
4, 3
12, 16
- Answer
-
48
30, 40
20, 30
- Answer
-
60
44, 55
In the following exercises, find the least common multiple of each pair of numbers using the prime factors method.
8, 12
- Answer
-
24
12, 16
28, 40
- Answer
-
280
84, 90
55, 88
- Answer
-
440
60, 72
Everyday Math
Writing a Check Jorge bought a car for $24,493. He paid for the car with a check. Write the purchase price in words.
- Answer
-
twenty-four thousand, four hundred ninety-three dollars
Writing a Check Marissa’s kitchen remodeling cost $18,549. She wrote a check to the contractor. Write the amount paid in words.
Buying a Car Jorge bought a car for $24,493. Round the price to the nearest
- ten
- hundred
- thousand; and
- ten-thousand.
- Answer
-
- $24,490
- $24,500
- $24,000
- $20,000
Remodeling a Kitchen Marissa’s kitchen remodeling cost $18,549, Round the cost to the nearest
- ten
- hundred
- thousand and
- ten-thousand.
Population The population of China was 1,339,724,852 on November 1, 2010. Round the population to the nearest
- billion
- hundred-million; and
- million.
- Answer
-
- 1,000,000,000
- 1,300,000,000
- 1,340,000,000
Astronomy The average distance between Earth and the sun is 149,597,888 kilometers. Round the distance to the nearest
- hundred-million
- ten-million; and
- million.
Grocery Shopping Hot dogs are sold in packages of 10, but hot dog buns come in packs of eight. What is the smallest number that makes the hot dogs and buns come out even?
- Answer
-
40
Grocery Shopping Paper plates are sold in packages of 12 and party cups come in packs of eight. What is the smallest number that makes the plates and cups come out even?
Writing Exercises
Give an everyday example where it helps to round numbers.
If a number is divisible by 2 and by 3 why is it also divisible by 6?
What is the difference between prime numbers and composite numbers?
- Answer
-
Answers may vary.
Explain in your own words how to find the prime factorization of a composite number, using any method you prefer.
Self Check
ⓐ After completing the exercises, use this checklist to evaluate your mastery of the objectives of this section.
ⓑ If most of your checks were:
…confidently. Congratulations! You have achieved the objectives in this section. Reflect on the study skills you used so that you can continue to use them. What did you do to become confident of your ability to do these things? Be specific.
…with some help. This must be addressed quickly because topics you do not master become potholes in your road to success. In math, every topic builds upon previous work. It is important to make sure you have a strong foundation before you move on. Who can you ask for help? Your fellow classmates and instructor are good resources. Is there a place on campus where math tutors are available? Can your study skills be improved?
…no—I don’t get it! This is a warning sign and you must not ignore it. You should get help right away or you will quickly be overwhelmed. See your instructor as soon as you can to discuss your situation. Together you can come up with a plan to get you the help you need.