Precision and greatest possible error in a measurement

Answer Key - Grade 9 Math Worksheet - Building Confidence

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

1. 1.

   Ari measures a crayon with a ruler and reads 12.5 cm. What is the smallest mark on the tool?

   • 0.01 cm
   • 1 cm
   • 10 cm
   • 0.1 cm
2. 2.

   Bo measures a ladder with a tape and reads 3.40 m. What is the smallest mark on the tool?

   • 1 m
   • 0.01 m
   • 0.1 m
   • 0.001 m
3. 3.

   Esme times a race with a stopwatch and reads 8.0 s. What is the smallest mark on the tool?

   • 1 s
   • 10 s
   • 0.01 s
   • 0.1 s
4. 4.

   Jun weighs a backpack on a scale and reads 7.25 kg. What is the smallest mark on the tool?

   • 0.01 kg
   • 0.1 kg
   • 0.001 kg
   • 1 kg
5. 5.

   Kira's kitchen scale is marked every 2 g. The greatest possible error is half of the smallest mark. What is it?

   1
6. 6.

   Luz's bathroom scale is marked every 0.5 kg. The greatest possible error is half of the smallest mark. What is it?

   0.25
7. 7.

   Milo's measuring cup is marked every 10 mL. The greatest possible error is half of the smallest mark. What is it?

   5
8. 8.

   Noah's stopwatch is marked every 0.2 s. The greatest possible error is half of the smallest mark. What is it?

   0.1
9. 9.

   Tala weighs a lemon on a scale as 120 g, to the nearest 10 g. The greatest possible error is 5 g. What is the smallest the true amount could be?

   115
10. 10.

    Zee times a sprint with a stopwatch as 6.25 s, to the nearest hundredth. The greatest possible error is 0.005 s. What is the smallest the true amount could be?

    6.245