Compare and order real numbers

Answer Key - Grade 8 Math Worksheet - Challenge Me

Circle the best answer, or write your answer on the line.

1. Read this first

   Use this

   Number line with a tick at every hundredth. Green marks are whole numbers, blue marks the other integers, orange marks the other rational numbers, and purple marks irrational numbers. Card A is √14, card B is 3 4/5, card C is 3.6, card D is 365%, card E is 3.7.

2. 1.

   Tala deals five number cards. Which order, from least to greatest, is right? Write the five letters.

   C, D, E, A, B

3. Use this

   Number line with a tick at every hundredth. Green marks are whole numbers, blue marks the other integers, orange marks the other rational numbers, and purple marks irrational numbers. Card A is π, card B is 22/7, card C is 3.1, card D is 3.2, card E is √10.

4. 2.

   Zee ranks five cards, two of them close to π. Which order, from greatest to least, is right? Write the five letters.

   D, E, B, A, C

5. Use this

   Number line with a tick at every hundredth. Green marks are whole numbers, blue marks the other integers, orange marks the other rational numbers, and purple marks irrational numbers. Card A is √2, card B is 1 2/5, card C is 142%, card D is 1.41, card E is 1.45.

6. 3.

   Ari sorts five number cards for a game. Which order, from least to greatest, is right? Write the five letters.

   B, D, A, C, E

7. Use this

   Number line with a tick at every thousandth. Green marks are whole numbers, blue marks the other integers, orange marks the other rational numbers, and purple marks irrational numbers. Card A is 4.2 × 10⁻¹, card B is 0.04, card C is 1/2, card D is 41%.

8. 4.

   Bo sorts four number cards. Which order, from least to greatest, is right? Write the four letters.

   B, D, A, C

9. Use this

   Number line with a tick at every thousandth. Green marks are whole numbers, blue marks the other integers, orange marks the other rational numbers, and purple marks irrational numbers. Card A is 7.2 × 10⁻¹, card B is 3/4, card C is 70%, card D is 0.073.

10. 5.

    Jun ranks four number cards. Which order, from greatest to least, is right? Write the four letters.

    B, A, C, D
12. 6.

    Noah compares a cube root with a decimal. Which is greater, ∛30 or 3.2?

    • ∛30 is greater.
    • They are equal.
    • 3.2 is greater.
13. 7.

    Pia checks a cube root against a decimal. Which is greater, ∛20 or 2.8?

    Use the picture in question 6.

    • They are equal.
    • 2.8 is greater.
    • ∛20 is greater.
14. 8.

    Ren tests a cube root against a decimal. Which is greater, ∛100 or 4.5?

    Use the picture in question 6.

    • They are equal.
    • ∛100 is greater.
    • 4.5 is greater.
15. 9.

    Tala explains a comparison on the board. Which reason shows that √50 is greater than 7?

    Use the picture in question 6.

    • √50 is about 5.
    • 7 × 7 = 49, and 50 is more than 49.
    • 50 is greater than 7.
    • A root sign makes a number bigger.
16. 10.

    Zee defends a comparison in math club. Which reason shows that √40 is less than 6.5?

    Use the picture in question 6.

    • √40 is about 7.
    • 40 is much bigger than 6.5.
    • A root is always smaller than a plain number.
    • 6.5 × 6.5 = 42.25, and 40 is less than 42.25.