For #43, I'm not sure where the 1/n came from or how 3/4 became 4/3.
Transcribed Image Text: 12:15 AM Wed Mar 16
70%
AA
A bartleby.com
Secondary Pro...
Free Chart - A...
- www.astro.co...
b The time requi...
* Favorites
Q SEARCH
& ASK AN EXPERT
CHAT
Vx MATH SOLVER
Expert Solution & Answer
Answer to Problem 43E
They will take 1- hours to mow a lawn working together.
Explanation of Solution
Given:
Time required by Julie = 2 hours
Time required by Husband = 4 hours
Approach:
As Julie can mow a lawn in 2 hours, the part of work she can do in one hour =.
As Julie's husband can mow a lawn in 4 hours, the part of work he can do in one hour =.
Now let's assume they can mow a lawn in 'n' hours working together.
Then the part of work they can do in one hour =-.
n
Calculation:
We have,
: = +
1
n
2
Solve this equation for n,
1
2 + 1
[LCM of (2, 4) = 4]
4
n
1
3
n
4
4
n =
3
3
Final Statement:
They will take 1, hours to mow a lawn working together.
< Previous
Next >
Chapter 1.2, Problem 42E
Chapter 1.2, Problem 44E
Got some follow up questions?
Date this solutien
Transcribed Image Text: Copyright 2017 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s).
Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it.
106
Chapter 1 Equations and Inequalities
25. Investment Jeffrey invested $16,000 in two accounts
paying 4% and 6% annual interest. If the total
interest earned in one year was $815, how much did
XXO
he invest at each rate?
26. Investment An executive invests $22,000, some at
7% and the rest at 6% annual interest. If he receives
an annual return of $1420, how much is invested at
XXO
each rate?
27. Financial planning After inheriting some money,
a woman wants to invest enough to have an
annual income of $5000. If she can invest $20,000
at 9% annual interest, how much more will she
have to invest at 7% to achieve her goal? (See the
table.)
36. Markup A merchant increases the wholesale cost
of a surfboard by 30% to determine the selling
price. If the surfboard sells for $588.90, find the
wholesale cost.
37. Break-point analysis A machine to mill a brass
plate has a setup cost of $600 and a unit cost of $3
for each plate manufactured. A bigger machine has
a setup cost of $800 but a unit cost of only $2 for
each plate manufactured. Find the break point.
Туре
Rate
Amount
Income
9% investment
0.09
20,000
.09(20,000)
7% investment
0.07
.07x
28. Investment A woman invests $37,000, part at 8%
and the rest at 9% annual interest. If the 95%
investment provides $452.50 more income than the
8% investment, how much is invested at each rate?
38. Break-point analysis A machine to manufacture
fasteners has a setup cost of $1200 and a unit cost
of $0.005 for each fastener manufactured. A newer
machine has a setup cost of $1500 but a unit cost
of only $0.0015 for each fastener manufactured.
Find the break point.
29. Investment Equal amounts are invested at 6%, 7%,
and 8% annual interest. If the three investments
39. Computer sales A computer store has fixed costs of
$8925 per month and a unit cost of $850 for every
computer it sells. If the store can sell all the comput-
ers it can get for $1275 each, how many must be sold
for the store to break even? (Hint: The break-even
point occurs when costs equal income.)
yield a total of $2037 annual interest, find the total
investment.
30. Investment Aaron invested equal amounts of
money at 5%, 7%, 9%, and 11% annual interest.
If the four investments yielded a total of
$1440 annual interest, find the total amount
40. Restaurant management A restaurant has fixed
costs of $137.50 per day and an average unit cost of
$4.75 for each meal served. If a typical meal costs
$6, how many customers must eat at the restaurant
each day for the owner to break even?
invested.
31. Ticket sales A full-price ticket for a college bas-
ketball game costs $2.50, and a student ticket costs
$1.75. If 585 tickets were sold, and the total receipts
were $1,217.25, how many tickets were student
tickets?
32. Ticket sales Of the 800 tickets sold to a movie,
480 were full-price tickets costing $7 each. If the
gate receipts were $4960, what did a student ticket
cost?
41. Roofing houses Kyle estimates that it will take him 7
days to roof his house. A professional roofer estimates
that it will take him 4 days to roof the same house.
How long will it take if they work together?
33. Discount An iPad Air is on sale for $413.08. What
was the original price of the iPad if it was dis-
counted 8%?
42. Sealing asphalt One crew can seal a parking lot in
8 hours and another in 10 hours. How long will it
take to seal the parking lot if the two crews work
together?
34. Discount After being discounted 20%, a weather
radio sells for $63.96. Find the original price.
35. Markup A business owner increases the wholesale
cost of a kayak by 70% and sells it for $365.50.
Find the wholesale cost.
43. Mowing lawns Julie can mow a lawn with a lawn
tractor in 2 hours, and her husband can mow the
same lawn with a push mower in 4 hours. How
long will it take to mow the lawn if they work
together?
Copyright 2017 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s).
Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it.
©Kalmatsuy/Shutterstock.com