Answer:
12/5hours=2.4 hours
Step-by-step explanation:
Sam:6hours
Tom:4hours
This is a rate problem
Sam's rate is one job completed in 6 hours which is 1/6
Tom's rate is one job completed in 4 hours which is 1/4
Together, they could complete 1/4+1/6 of the job in y hours
We are trying to find the rate at which Sam and Tom could complete the job together, or one job in x days, for a rate of 1/y
1/4+1/6=1/y
The least common denominator is 12y
Multiplying through by the LCD which gives:
12y(1/4)+ 12y (1/6)= 12y (1/y)
3y + 2y=12
5y = 12
y=12/5 hours=2.4hours
Therefore it will take 12/5 hours or 2.4 hours to complete the job if they work together
