Name _______________________

5.5 Multiplying and Dividing by Decimal Powers of Ten

Use mental math to multiply each decimal by a whole number power of ten.

1. 3.4  10  ______

2. 3.45  100  ______

3. .56  10  ______

4. 1.234  1000  ______

5. 87.9  100  ______

6. 98.32  10  ______

7. 7.2  1000  ______

Use mental math to multiply each decimal by a decimal power of ten.

8. 3.2  .10  ______

9. 0.678  .100  ______

10. 2.123  .10  ______

11. 0.890  .1000  ______

12. 5  .10  ______

13. 7.7  .100  ______

14. 12  .10  ______

15. 456.8  .100  ______

Use mental math to divide each decimal by a power of ten.

16. 3.4  10  ______

17. 67.89  100  ______

18. 32.10  10  ______

19. 0.567  100  ______

20. 0.87  1000  ______

Use mental math to divide each decimal by a decimal power of ten.

21. 6.7  .10  ______

22. 0.654  .100  ______

23. 2.1  .10  ______

24. 4.32  .1000  ______

25. 0.98765  .10  ______

Write each decimal in scientific notation.

26. 0.00056

27. 0.0098

28. 0.024

29. 0.000023

30. 0.00000045