SOLUTION: By increasing her usual speed by 25 kilometers per hour, a bus driver decreases the time on a 25-kilometer trip by 10 minutes. Find the usual speed.
The Vilas County News ear
Algebra.Com
Question 499020: By increasing her usual speed by 25 kilometers per hour, a bus driver decreases the time on a 25-kilometer trip by 10 minutes. Find the usual speed.
The Vilas County News earns a profit of $20 per year for each of its 3,000 subscribers. Management projects that the profit per subscriber would increase by 1¢ for each additional subscriber over the current 3,000. How many total subscribers are needed to bring a total profit of $113,100?
Perform the operations and simplify. 1/x times x^2-15x all over x-14
Answer by ankor@dixie-net.com(22740) (Show Source): You can put this solution on YOUR website!
By increasing his usual speed by 25 kilometers per hour, a bus driver decreases the time on a 25-kilometer trip by 10 minutes.
Find the usual speed.
:
Let s = his usual speed
Change 10 min to 1/6 hr
write a time equation; time = dist/speed
Usual time - 10 min = faster time
- =
multiply by 6s(s+25), results
6(s+25)*25 - s(s+25) = 6s*25
150(s+25) - s^2 - 25s = 150s
150s + 3850 - s^2 - 25s = 150s
Combine as a quadratic equation on the right
0 = s^2 + 25s - 3750
Factors to
(x-50)(x+75) = 0
Positive solution
x = 50 mph is his usual speed
:
:
The Vilas County News earns a profit of $20 per year for each of its 3,000 subscribers.
Management projects that the profit per subscriber would increase by 1¢ for each additional subscriber over the current 3,000.
How many total subscribers are needed to bring a total profit of $113,100?
:
Find the present profit: 3000 * $20 = $60000
then: 113100 - 60000 = $53,100 increase in profits
Let n = number of subscribers over 3000 to increase profit by 1 cent for each
.01n = 53100
n =
n = 5,310,000 additional subscribers, doesn't seem very realistic, does it!
:
:
Perform the operations and simplify.
*
------------
(x - 14)
:
*
------------
(x - 14)
:
Cancel the x and you are left with
RELATED QUESTIONS
By increasing her usual speed by 25 kilometers per hour, a bus driver decreases the time... (answered by lwsshak3)
By increasing her usual speed by 25 kilometers per hour, a bus driver decreases the time... (answered by mananth)
Question: By increasing her usual speed by 25 kilometers per hour, a bus driver decreases (answered by orca)
A tour bus normally leaves for its destination at
5:00 p.m. for a 300 mile trip. This... (answered by ikleyn,ewatrrr)
a bus leaves at 5.00pm for a 273 mile trip to vegas.this week it left at 5:15pm.to... (answered by mananth)
A tour bus normally leaves for its destination at 5:00 p.m. for a 330 mile trip. This... (answered by josmiceli)
A tour bus normally leaves for its destination at 5:00 p.m. for a 378 mile trip. This... (answered by ikleyn,josgarithmetic,mananth,greenestamps)
a Tour bus leaves Sacramento every Friday evening at 5 pm for a 170 mile trip. this week (answered by richwmiller,josmiceli,solver91311)
A tour bus leaves Sacramento every Friday evening at 5:00 P.M. for a 264-mile trip to Las (answered by lwsshak3)