SOLUTION: machine A & B always operate independently and at their respective constant rates. when working alone, machine A can fill a production lot in 5hours, and machine B can fill the sam

Algebra ->  Expressions-with-variables -> SOLUTION: machine A & B always operate independently and at their respective constant rates. when working alone, machine A can fill a production lot in 5hours, and machine B can fill the sam      Log On


   

Question 1015840: machine A & B always operate independently and at their respective constant rates. when working alone, machine A can fill a production lot in 5hours, and machine B can fill the same lot in X hours. When the two machines operate simultaneously to fill the production lot, it takes them 2hours to complete the job.. what is the value oF X?.
Found 2 solutions by josgarithmetic, FrankM:
Answer by josgarithmetic(39615) About Me  (Show Source):
You can put this solution on YOUR website!
A    1/5
B    1/x
A&B  1/2

1%2F5%2B1%2Fx=1%2F2 because the rate of A and B combined is the sum of the individual rates.

Answer by FrankM(1040) About Me  (Show Source):
You can put this solution on YOUR website!
Machine A fills .2 lots/hr Machine B fills 1/X lots per hour.
.2+(1/X) lots per hour total.
If together they fill .5 lots per hour, then .5-.2=.3
so 1/X = .3 or 3 1/3 hours per lot.