Question

1
Secondary SchoolMath 13 points


Farhan worked for 2 hours and then raju joined him. after 4 more hours, farhan stopped, and raju took another 20 hours to complete the remaining part of the job. if both of them work together they can complete the job in 18 hours. how many hours will farhan and raju take to complete the job if they work separately?

Answer 1

$\huge{\bold{\red{SOLUTION}}}}$

Let farhan takes X hour to complete the work

so he did 6/X in 6 hours


Let Raju .............Y hour to

so he did 24/Y of work in 24 hours.


ATQ

6/X+24/Y =1.... 1.........×1


1/X +1/Y = 1/18. ......2........×6

6/X +24/Y =1.

6/X +6/Y =1/3

subtracting eq 2 from 1


18/Y =2/3

Y=27
putting value of X in equation (2)

1/X= 1/18 -1/27

1/X=1/54

X=54


Farhan alone can complete the work in 54 hours
Raju alone can complete the work in 27 hours.

$\huge{\bold{\boxed{\red{Farhan\:-54 hours}}}}$

$\huge{\bold{\boxed{\red{Raju\:-27 hours}}}}$