SOLVING EQUATIONS Multiply by a reciprocal to solve the equation.
Student Help
HOMEWORK HELP
NE
ER T
INT
Extra help with
problem solving in
Exs. 37–45 is available at
www.mcdougallittell.com
3
37. k 1
4
2
38. y 4
5
7
39. 0 x
8
1
40. y 6
3
5
41. 10 x
6
5
42. m 20
8
2
43. 12 x
3
3
44. x 6
7
4
45. x 36
5
ERROR ANALYSIS In Exercises 46 and 47, find and correct the error.
2
x = 10
5
46.
47.
冉52冊冉52x冊 = 10
3
4
– x = 6
冉 冊
4 3
4
– x = (6)
3 4
3
x = 10
x=8
MODELING REAL-LIFE PROBLEMS In Exercises 48 and 49, use the verbal
model to write a linear equation. Then use the multiplication property of
equality to solve the equation.
48. It takes 45 peanuts to make one ounce of peanut butter. How many peanuts
will be needed to make a 12-ounce jar of peanut butter?
1Number of peanuts1
Number of peanuts per ounce
Number of ounces
49. You ate 3 of the 8 slices of a pizza. You paid $3.30 as your share of the total
cost of the pizza. How much did the whole pizza cost?
Science
1Number of pieces you ate1
p Cost of the Your share
whole pizza
of the cost
Total number of pieces
50. BUNDLING NEWSPAPERS You are loading a large pile of newspapers onto
a truck. You divide the pile into four equal-size bundles. One bundle weighs
37 pounds. You want to know the weight x of the original pile. Which
equation represents this situation? Solve the correct equation.
x
A. 37
4
B. 4x 37
C. 37x 4
51. MAIL DELIVERY Each household in the United States receives about
THUNDERSTORMS You see
lightning almost at the instant
it flashes since light travels
so quickly. You hear the
thunder later because sound
takes about 5 seconds to
travel a mile near the ground.
142
Chapter 3
676 pieces of junk mail per year. If there are 52 weeks in a year, then
about how many pieces of junk mail does a household receive per week?
HINT: Let x the number of pieces of junk mail received per week. Solve
the equation 52x 676.
52.
You can tell about how many miles you are from a
thunderstorm by counting the seconds between seeing the lightning and
hearing the thunder, and then dividing by five. How many seconds would you
count for a thunderstorm that is nine miles away?
Solving Linear Equations