A company has two types of machines, type R and type S.
A company has two types of machines, type R and type S. Operating at a constant rate, a machine of type R does a certain job in 49 hrs and a machine of type S does the same job in 14 hours. If the company used the same number of each type of machine to do the job in 2 hours, how many machines of type R were used?
Answer/Solution
49/9
Steps/Work
Rate of machine R =1/49
Rate of machine S =1/14
since same no of machines used for R and S to do the same work in 2 hrs
So collective rate needed to finish the work in 2 hrs= 1/2
Let the no of machine be x
So, x/49 +x/14 =1/2
9x=49
x=49/9
So no of machine R is 49/9
Answer A
Rate of machine S =1/14
since same no of machines used for R and S to do the same work in 2 hrs
So collective rate needed to finish the work in 2 hrs= 1/2
Let the no of machine be x
So, x/49 +x/14 =1/2
9x=49
x=49/9
So no of machine R is 49/9
Answer A