SOLUTION: After a certain number of days, a bicycle factory had produced 400 bicycles. In the next 3days, the factory produced 37 bicycles and lowered its average number of bicycles produced
Question 967245: After a certain number of days, a bicycle factory had produced 400 bicycles. In the next 3days, the factory produced 37 bicycles and lowered its average number of bicycles produced per day by 1. What was its final average? Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website! After a certain number of days, a bicycle factory had produced 400 bicycles.
In the next 3days, the factory produced 37 bicycles and lowered its average number of bicycles produced per day by 1.
What was its final average?
:
let d = the "certain number of days
then = the original daily average
: = final average
:
original av - final av = 1 = = 1
multiply equation by d(d+3), cancel the denominators and we have
400(d+3) - 437d = d(d+3)
400d + 1200 - 437d = d^2 + 3d
1200 - 37d = d^2 + 3d
Arrange to form a quadratic equation on the right
0 = d^2 + 3d + 37d - 1200
d^2 + 40d - 1200 = 0
Factors to
(d+60)(d-20) = 0
d = 20 the certain number of days
then
23 days for the final average
therefore = 19 bikes a day is the final average
:
:
Confirm this by finding the original average: 400/20 = 20 bikes a day
