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.

   Noah needs √7 to the nearest hundredth. What is √7 to the nearest hundredth?

   2.65
3. 2.

   Pia estimates √90 to the nearest hundredth. What is √90 to the nearest hundredth?

   9.49
4. 3.

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

   5.92
5. 4.

   Ari cuts a square poster with an area of 94 square inches. About how long is each side, to the nearest tenth of an inch?

   9.7
7. 5.

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

   -4.5
8. 6.

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

   Use the picture in question 5.

   -3.9
9. 7.

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

   • 6 and 7
   • 10 and 11
   • 9 and 10
   • 3 and 4
10. 8.

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

    • 3.1
    • 9.8
    • 6.3
    • 9.9
12. 9.

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

    • 15 and 16
    • 14 and 15
    • 115 and 116
    • 16 and 17
13. 10.

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

    Use the picture in question 9.

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