You will now practice all the skills you learned in Unit 1. Check your work using the answer key at the end of the review.

1. Write the place value names (ones, tens, hundreds, thousands, ten thousands, hundred thousands, millions) for each bolded digit.
   1. 4392
   2. 765
   3. 18293
   4. 56428
   5. 3641758
   6. 426153
   7. 8429576
   8. 4258
2. Using the number 349285106, write the digit that is in each of the following place values.
   1. millions
   2. ones
   3. ten thousands
   4. thousands
   5. hundreds
   6. hundreds thousands
   7. tens
3. Underline the digit for the place value named.
   1. hundreds,    5321
   2. tens,    8703
   3. ten thousands,    34891
   4. hundred thousands,    891402
   5. thousands,    72491
   6. millions,    4201856
4. Write the word names for the numbers.
   1. 818
   2. 1678
   3. 29764
   4. 1984152
   5. 42803
   6. 226917
5. Write the numerals for these word names.
   1. twenty-five thousand one hundred thirty-two
   2. one thousand two hundred seven
   3. two hundred fifteen thousand twenty-four
   4. one million six hundred ninety-five thousand four hundred twenty
   5. seven hundred twenty-six
   6. nine thousand four
6. Write each number in expanded form.
   1. 184
   2. 3908
   3. 61281
   4. 1539587
   5. 366524
7. Write each number from expanded form.
   1. 50000  +  6000  + 600  +  90  + 8
   2. 200000  +  70000  +  8000  +  200  +  60  + 1
   3. 3000  +  800  +  80  + 5
   4. 1000000 + 400000 + 70000 + 6000 + 100 + 50 + 3
   5. 700  +  1
8. Arrange these numbers in order from smallest to largest.
   1. 18; 34937; 727; 1487; 147832
   2. 769; 6790; 697; 76976; 76796
9. Write <, >, or = in each blank as needed.
   1. 9698          6899
   2. 7542         7452
   3. 34682         39421
   4. 124693         124693
   5. 738423         783423
   6. 45832         54123
10. Round each number to the nearest hundred.
    1. 774
    2. 2581
    3. 21204
    4. 692
    5. 572098
    6. 7652931
11. Round each number to the nearest thousand.
    1. 948
    2. 75767
    3. 288869
    4. 479
    5. 3976
    6. 5012
12. Round each number to the nearest ten thousand.
    1. 4028
    2. 226917
    3. 126804
    4. 9794487
    5. 87805
    6. 5912
13. Round each number to the nearest hundred thousand.
    1. 687029
    2. 1326876
    3. 523715
    4. 4766883
    5. 8182390
    6. 792013
14. Round each number to the nearest million.
    1. 1009627
    2. 28101052
    3. 894063
    4. 9778656
    5. 80379591
    6. 3102975
15. Word Problems.
    1. The three heaviest sharks are the whale shark weighing 30500 kilograms. The basking shark weighing 9258 kilograms. The great white shark weighing 3507 kilograms. Round each number to the nearest thousand.
       

       Shark	Number	Rounded Number
       Whale shark
       Basking shark
       Great White Shark

    2. Three of the largest islands in the world are New Guinea covering 785753 square kilometers, Baffin Island covering 503944 square kilometers and Honshu Island covering 227413 square kilometers. Round each number to the nearest ten thousand.
       

       Island	Number	Rounded Number
       New Guinea
       Baffin Island
       Honshu Island

Answers to Unit 1 Review – Number Sense

1. 1.  tens
   2. ones
   3. thousands
   4. hundreds
   5. hundred thousands
   6. ten thousands
   7. millions
   8. thousands
2. 1. 2
   2. 6
   3. 8
   4. 5
   5. 1
   6. 2
   7. 0
3. 1. 5321
   2. 8703
   3. 34891
   4. 891402
   5. 72491
   6. 4201856
4. 1. eight hundred eighteen
   2. one thousand six hundred seventy-eight
   3. twenty-nine thousand seven hundred sixty-four
   4. one million nine hundred eighty-four thousand one hundred fifty-two
   5. forty-two thousand eight hundred three
   6. two hundred twenty-six thousand nine hundred seventeen
5. 1. 25132
   2. 1207
   3. 215024
   4. 1695420
   5. 726
   6. 9004
6. 1. 100 + 80 + 4
   2. 3000 + 900 + 8
   3. 60000 + 1000 + 200 + 80 + 1
   4. 1000000 + 500000 + 30000 + 9000 + 500 + 80 + 7
   5. 300 000 + 60 000 + 6 000 + 500 + 20 + 4
7. 1. 56698
   2. 278261
   3. 3885
   4. 1476153
   5. 701
8. 1. 18,  727,  1487,  34937,  147832
   2. 697,  769,  6790,  76796,  76976
9. 1. >
   2. >
   3. <
   4. =
   5. <
   6. <
10. 1. 800
    2. 2600
    3. 21200
    4. 700
    5. 572100
    6. 7652900
11. 1. 1000
    2. 76000
    3. 289000
    4. 0
    5. 4000
    6. 5000
12. 1. 0
    2. 230000
    3. 130000
    4. 9790000
    5. 90000
    6. 10000
13. 1. 700000
    2. 1300000
    3. 500000
    4. 4800000
    5. 8200000
    6. 800000
14. 1. 1000000
    2. 28000000
    3. 1000000
    4. 10000000
    5. 80000000
    6. 3000000

15. 1. Shark	Number	Rounded Number
       Whale shark	30500	31000
       Basking shark	9258	9000
       Great White Shark	3507	4000

    2. Kilometers	Number	Rounded Number
       New Guinea	785753	790000
       Baffin Island	503944	500000
       Honshu Island	227413	230000