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: 3 × 10^6 B: 8 × 10^3 C: 5 × 10^6 D: 1.2 × 10^4” Tala'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, A, C
3. 3.

   “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
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 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
6. 6.

   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
7. 7.

   Noah's phone calculator shows 45 × 10^3, but the first part has two digits. How do you write the same number in scientific notation?

   4.5 × 10^4
8. 8.

   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
9. 9.

   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
10. 10.

    Bo's robot prints 9.2 × 10^-4 and waits. Only one choice matches it. Which number is equal to 9.2 × 10^-4?

    • 92,000
    • 0.000092
    • -0.00092
    • 0.00092