A carpenter can do a job in two hours. His assistant can do the same job in three hours. How long would it take them to do the job together?PLZ HELP

Question

asked Oct 21, 2019 3.0k views

1 Answer

Jonathan Nielsen · Answer 1 · 2019-10-27T03:45:37+0000

Answer:
$1(1)/(5)\text{ hours}$

Explanation:

Given : A carpenter can do a job in two hours.

i.e. rate of work done by carpenter per hour=
(1)/(2) (1)

Also, His assistant can do the same job in three hours.

i.e. rate of work done by assistant per hour=
(1)/(3) (2)

Let t be the time taken by both of them if they work together , then we have

(1)/(t)=(1)/(2)+(1)/(3) [Adding (1) and (2)]

$\Rihtarrow\ (1)/(t)=(3+2)/(6)=(5)/(6)\\\\\Rightarrow\ t=(6)/(5)\text{ hour}\\\\\Rightarrow\ t=(6)/(5)=1(1)/(5)\text{ hours}$

Hence, it would take
$1(1)/(5)\text{ hours}$ to them to do the job together.