Write a variable expression to represent the phrase.
17. The sum of a number and 7
18. 11 fewer than a number
19. The quotient of a number and 6
20. A number times 8
21. 5 less than a number
22. 5 divided into a number
23. You can evaluate the expression 112 p to find the number of pencils you have left from a package of 112 pencils after you have distributed p pencils among your classmates. Find the number of pencils left over after distributing 56 pencils. 24. You buy 5 shirts each having the same price. Write a variable expression for the total amount you spend on the shirts. How much money do you spend on the shirts when each shirt costs $15?
25. Write a variable expression for a team’s final score. 26. Find each team’s final score. 27. Another team earns 175 points in the verbal section. At least how many points must the team earn in the math section to have a higher final score than teams A, B, and C?
In Exercises 25–27, use the double bar graph that shows three teams’ scores in an academic competition. A team’s final score is the sum of the points for the verbal section v and the math section m.
250 200 150 100 50 0
A
B Team Verbal
C Math
Pre-Algebra Chapter 1 Resource Book
5
Answers Challenge Practice 1. 13.8
Practice A 1. 11
2. 16
7. 50
8. 7
3. 45 9. 1
4. 4 10. 10
5. 17 11. 12
6. 31 12. 3
15. 61 16. 17 17. n 7 n 18. n 11 19. 20. n p 8 21. n 5 6 n 22. 23. 56 24. 5s; $75 25. v m 5 26. 250; 300; 350 27. 176 13. 7
14. 21
1. 4
2. 30
3. 14
4. 25
5. 19
7. 42
8. 6
9. 90
10. 2
11. 17
14. 50
15. 160
18. 27 n
19. 29 n
21. 16 n
22. 7n
26.
16. 4
20. n 6 42 56 23. 24. n n
Cost (dollars)
Amount left (dollars)
1
7
343
2
14
336
3
21
329
4
28
322
28. 350 7b
6. 48
12. 22 130 17. g
Books
27. 7b
6. 27
7. 90
25. 12n
1. 3.5
2. 3.17
6. 37.7
7. 85
3. 7.5 8. 20
4. 0.3 9. 8
6. n8
2. 185 7. 64
8. 256
4. (1.2)2
9. 4096
5. c7
10. 0.8
12. 0.64 13. 19 squared; 19 p 19 361 14. 20 cubed; 20 p 20 p 20 8000 15. 0.7 cubed; 0.7 p 0.7 p 0.7 0.343 16. 2.4 squared; 2.4 p 2.4 5.76 17. 3.2 cubed; 3.2 p 3.2 p 3.2 32.768 18. 0.6 to the fourth power; 0.6 p 0.6 p 0.6 p 0.6 0.1296 19. 11 to the fourth power; 11 p 11 p 11 p 11 14,641 20. 9 to the fifth power; 9 p 9 p 9 p 9 p 9 59,049 21. 10,000 22. 100,000 23. 1,000,000 24. 0.0144 25. 0.001728 26. 0.12 27. 196 m2 28. 6.25 ft2 29. 9.261 in.3 30. 216 cm3