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Math Grade 4-5 Answer Key

Math: Simplifying Fractions to Lowest Terms

Use common factors to write equivalent fractions

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Math: Simplifying Fractions to Lowest Terms

Use common factors to write equivalent fractions

Math - Grade 4-5

Instructions: Read each problem carefully. Find a common factor for the numerator and denominator, then simplify the fraction to lowest terms. Show your work in the space provided.
  1. 1

    Simplify 6/8 to lowest terms.

    Find the greatest common factor of 6 and 8.

    6/8 simplifies to 3/4 because both 6 and 8 can be divided by 2, and 3 and 4 have no common factor greater than 1.
  2. 2

    Simplify 10/15 to lowest terms.

    10/15 simplifies to 2/3 because both 10 and 15 can be divided by 5.
  3. 3

    Simplify 12/18 to lowest terms.

    List factors of 12 and 18, then choose the greatest factor they share.

    12/18 simplifies to 2/3 because the greatest common factor of 12 and 18 is 6, and 12 ÷ 6 = 2 while 18 ÷ 6 = 3.
  4. 4

    A class has 9 students wearing blue shirts out of 12 students total. Write the fraction of students wearing blue shirts in lowest terms.

    The fraction is 9/12, which simplifies to 3/4 because both 9 and 12 can be divided by 3.
  5. 5

    Simplify 14/21 to lowest terms.

    Think of the 7 times table.

    14/21 simplifies to 2/3 because both 14 and 21 can be divided by 7.
  6. 6

    Simplify 16/20 to lowest terms.

    16/20 simplifies to 4/5 because both 16 and 20 can be divided by 4.
  7. 7

    Which fraction is 8/12 in lowest terms: 4/6, 2/3, or 1/2? Explain your choice.

    A fraction is in lowest terms when the top and bottom do not share a factor greater than 1.

    8/12 in lowest terms is 2/3 because dividing both 8 and 12 by 4 gives 2/3, and 2 and 3 have no common factor greater than 1.
  8. 8

    Simplify 18/24 to lowest terms.

    18/24 simplifies to 3/4 because the greatest common factor of 18 and 24 is 6.
  9. 9

    Simplify 25/30 to lowest terms.

    Numbers ending in 0 or 5 are divisible by 5.

    25/30 simplifies to 5/6 because both 25 and 30 can be divided by 5.
  10. 10

    A garden has 6 tomato plants out of 10 total plants. Write the fraction of tomato plants in lowest terms.

    The fraction is 6/10, which simplifies to 3/5 because both 6 and 10 can be divided by 2.
  11. 11

    Simplify 27/36 to lowest terms.

    Use the greatest common factor of 27 and 36.

    27/36 simplifies to 3/4 because both 27 and 36 can be divided by 9.
  12. 12

    Is 5/7 already in lowest terms? Explain your answer.

    Yes, 5/7 is already in lowest terms because 5 and 7 have no common factor greater than 1.
  13. 13

    Simplify 20/28 to lowest terms.

    Both numbers are even, but you may be able to divide by a larger common factor than 2.

    20/28 simplifies to 5/7 because both 20 and 28 can be divided by 4.
  14. 14

    A ribbon is divided into 16 equal sections. 12 sections are colored green. Write the green part of the ribbon as a fraction in lowest terms.

    The green part is 12/16, which simplifies to 3/4 because both 12 and 16 can be divided by 4.
  15. 15

    Simplify 30/45 to lowest terms and explain the steps you used.

    Look for the largest number that divides both 30 and 45 evenly.

    30/45 simplifies to 2/3 because the greatest common factor of 30 and 45 is 15, so 30 ÷ 15 = 2 and 45 ÷ 15 = 3.
LivePhysics™.com Math - Grade 4-5 - Answer Key