Basic Math and Pre-Algebra

PART 5. Extra Practice


Your journey through the world of numbers is coming to a close. I hope it was a good trip for you. Was it perfect? No? Well, I suppose it’s rare that any trip is perfect. After any trip, no matter how wonderful, you tend to come home thinking of what you’ll do next time.

Welcome to next time. If you want to make your math world tour better, you need to make your skills stronger. Did you have trouble with some of the topics? Practice. This part contains extra problems based on the material in each of the previous parts. You can use them all to keep your skills strong, or focus on the problems that correspond to topics you found difficult. Answers are provided in Appendix B, so you can check your work as you go along.


CHAPTER 21. Extra Practice


Part I: Arithmetic


Use the number 8,472,019 to answer questions 1-5.

1. Name the digit in the hundreds place.

2. Name the digit in the hundred-thousands place.

3. Name the digit in the thousands place.

4. Name the digit in the tens place.

5. Name the digit in the millions place.


Write each number in scientific notation.

6. 7,300

7. 12,000

8. 903

9. 2,450,000

10. 691,000


Evaluate each expression.


Find the following:

21. The prime factorization of 280.

22. The prime factorization of 5,005.

23. The GCF of 510 and 272.

24. The LCM of 91 and 119.

25. The GCF and the LCM of 42 and 90.


Perform each calculation.



Use a proportion to solve each problem.

36. If 6 plants require 4.5 ounces of water, how much water will 27 of the same type of plant need?

37. The ratio of dark chocolate candies to milk chocolate candies in a particular mixture is 3 to 7. If you buy 5 pounds of the mixture, how many pounds of dark chocolate candies will it contain?

38. A certain rye bread recipe calls for 4 cups of wheat flour and 3 cups of rye flour. You have a 5-pound sack of rye flour, which measures out to 22.5 cups, and you’d like to use it all. How much wheat flour will you need?

39. Jeff is ordering food for a Super Bowl party. The caterer’s brochure says that 6 gallons of chili will feed 40 people. If 100 people are expected at the party, how much chili should Jeff order?

40. Leslie designed a drapery panel that is made from 2 yards of print fabric and 5.5 yards of solid fabric. To cover all the windows in her living room, she will need 90 yards of fabric in total. How many yards of solid fabric should she order?



41. What is 18% of 45?

42. Thirty-three is what percent of 110?

43. 38 is 16% of what number?

44. What is the percent decrease in the price of a rug that originally sold for $850 and is on sale for $629?

45. A mountain bike that originally sold for $600 increases in price to $675. What is the percent increase in the price?