Extra Set

Grade 8 · Unit 5 · L21 · Version A · 7354

Integer powers of 10

Name ________________

Date ________________

Period ________________

1.
Write 5 × 10^4 as an ordinary number.
Answer. 50000
Move the decimal 4 places right: 50000.
2.
Write 5 × 10^4 as an ordinary number.
Answer. 50000
Move the decimal 4 places right: 50000.
3.
Write 400 as a product of a digit and a power of 10.
Answer. 4 × 10^2
400 = 4 × 10^2.
4.
Write 9 × 10^5 as an ordinary number.
Answer. 900000
Move the decimal 5 places right: 900000.
5.
Write 400000 as a product of a digit and a power of 10. Then Ava needs 4 of that amount. What is the total they need?
Answer. 16 × 10^5
400000 = 4 × 10^5. Then multiply by 4: 16 × 10^5.
6.
Write 3 × 10^3 as an ordinary number. Then Jonah needs 5 of that amount. What is the total they need?
Answer. 15000
Move the decimal 3 places right: 3000. Then multiply by 5: 15000.
7.
Write 3 × 10^5 as an ordinary number. Then Sam needs 2 of that amount. What is the total they need?
Answer. 600000
Move the decimal 5 places right: 300000. Then multiply by 2: 600000.
8.
Write 5 × 10^5 as an ordinary number. Then Grace needs 2 of that amount. What is the total they need?
Answer. 1000000
Move the decimal 5 places right: 500000. Then multiply by 2: 1000000.
9.
Write 9 × 10^3 as an ordinary number. Then Ava needs 5 of that amount. What is the total they need?
Answer. 45000
Move the decimal 3 places right: 9000. Then multiply by 5: 45000.
10.
Write 5000 as a product of a digit and a power of 10. Then Sam needs 5 of that amount. What is the total they need?
Answer. 25 × 10^3
5000 = 5 × 10^3. Then multiply by 5: 25 × 10^3.
11.
Think
Elena tried this problem:
Write 7 × 10^3 as an ordinary number.
Elena wrote 14000. That is not correct. What is the right answer?
Answer. 7000
Elena’s answer 14000 is off. Move the decimal 3 places right: 7000.
12.
Think
Jonah tried this problem:
Write 200 as a product of a digit and a power of 10.
Jonah wrote 1 × 10^2. That is not correct. What is the right answer?
Answer. 2 × 10^2
Jonah’s answer 1 × 10^2 is off. 200 = 2 × 10^2.

Original extra practice. Keys are computed from the items, not guessed.

L21 · Integer powers of 10