Powers of ten and scientific notation

Answer Key - Grade 7 Math Worksheet - Challenge Me

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

1. 1.

   “A: 4 × 10^5 B: 9 × 10^2 C: 2.5 × 10^5 D: 7 × 10^3” Ren's science notes list four numbers. Write the letters with commas, like P, Q, R, S. What is the order from least to greatest?

   B, D, C, A
2. 2.

   “A: 4 × 10^-3 B: 6 × 10^-5 C: 2 × 10^-3 D: 9 × 10^-1” Zee's science notes list four numbers. Write the letters with commas, like P, Q, R, S. What is the order from least to greatest?

   B, C, A, D
3. 3.

   “A: 6 × 10^2 B: 2 × 10^-2 C: 4 × 10^-3 D: 1.6 × 10^1” Ari's science notes list four numbers. Write the letters with commas, like P, Q, R, S. What is the order from least to greatest?

   C, B, D, A
4. 4.

   “A: 0.0035 B: 2 × 10^-2 C: 9 × 10^-4 D: 5 × 10^-3” Esme's notes list four numbers, and one is not in scientific notation. Write the letters with commas, like P, Q, R, S. What is the order from least to greatest?

   C, A, D, B
5. 5.

   A leaf is 0.00034 m thick, and Kira pressed it flat in a book. How do you write 0.00034 in scientific notation?

   3.4 × 10^-4
6. 6.

   A thin sheet of ice on a puddle is 0.0062 m thick, and Luz taps it gently. How do you write 0.0062 in scientific notation?

   6.2 × 10^-3
7. 7.

   A shell is 0.038 m long, and Milo found it at the beach. How do you write 0.038 in scientific notation?

   3.8 × 10^-2
8. 8.

   The TV screen in Pia's game room shows 0.35 × 10^5 points, but the first part is less than 1. How do you write the same number in scientific notation?

   3.5 × 10^4
9. 9.

   A butterfly's body is 0.4 × 10^-2 m wide, and Ren drew it carefully. The first part is less than 1. How do you write the same number in scientific notation?

   4 × 10^-3
10. 10.

    Zee needs the standard form of 3.4 × 10^-2. One choice is right and the others are sneaky. Which number is equal to 3.4 × 10^-2?

    • 0.034
    • -0.034
    • 0.0034
    • 340