Problema Solution
andres and biloy, working together, can build a chicken house in 6 2/3 hours. andres became ill after 3 hours of working together with biloy, and biloy finished the job, continuing to work alone, in 8 1/4 more hours. how long would it take each working alone to do the job?
Answer provided by our tutors
let
a = the number of hours andreas needs to finish the job alone
1/a = the rate of for per hour of andreas
b = the number of hours biloy needs to finish the job alone
1/b = the rate of for per hour of biloy
andres and biloy, working together, can build a chicken house in 6 2/3 hours or 6 2/3 = 20/3 hours
1/(20/3) = 3/20 the together rate
8 1/4 = (4*8+1)/4 = 33/4
3*(3/20) + (33/4)(1/b) = 1
by solving we find:
b = 15 hr
click here to see the step by step solution of the equation:
biloy needs 15 hours to finish the job alone.
1/a + 1/b = 3/20
1/a + 1/15 = 3/20
by solving we find:
a = 12 hr
click here to see the step by step solution of the equation:
andres needs 12 hours the finish the job alone.