Estimate and place square roots and pi on a number line

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.

2. 1.

   Ren rounds √35 to two decimal places. What is √35 to the nearest hundredth?

   5.92
3. 2.

   Tala plants a square garden bed with an area of 75 square feet. About how long is each side, to the nearest tenth of a foot?

   8.7
5. 3.

   Bo plots a negative root. What is −√20 to the nearest tenth?

   -4.5
6. 4.

   Esme estimates a negative root for a game. What is −√15 to the nearest tenth?

   Use the picture in question 3.

   -3.9
8. 5.

   Kira squares the number π for a puzzle, and a pizza sits nearby. Between which two whole numbers is π²?

   • 6 and 7
   • 3 and 4
   • 9 and 10
   • 10 and 11
9. 6.

   Luz squares π on a calculator. Which whole number is π² closer to?

   Use the picture in question 5.

   • 6
   • 3
   • 9
   • 10
10. 7.

    Milo squares π with a coin in hand. Using π = 3.14, what is π² to the nearest tenth?

    • 6.3
    • 9.8
    • 9.9
    • 3.1
12. 8.

    Noah has a big square to place, √230. Between which two whole numbers is √230?

    • 115 and 116
    • 16 and 17
    • 14 and 15
    • 15 and 16
13. 9.

    Pia reads √300 on a calculator. Between which two whole numbers is √300?

    Use the picture in question 8.

    • 150 and 151
    • 18 and 19
    • 17 and 18
    • 16 and 17
14. 10.

    Ren needs √350 for a project. Between which two whole numbers is √350?

    Use the picture in question 8.

    • 17 and 18
    • 19 and 20
    • 175 and 176
    • 18 and 19