Question

Thomas takes 7 days to paint a house completely whereas require 9 days to paint the same house completely. how many days will take to paint the house if both them work together?

Answer 1

let the average to complete the painting of house = 8 days
let the thomas required x
the rohan required x +2
x+ x +2 = 8
2x +2 =8
=3 days

Answer 2

Answer:

Both will paint the house completely in 4 days.

Step-by-step explanation:

Let both will paint the house completely in t days.

The part of house painted by both in one day is $\frac{1}{t}$.

Thomas takes 7 days to paint a house completely.

The part of house painted by Thomas in one day is $\frac{1}{7}$.

Second person takes 9 days to paint a house completely.

The part of house painted by second person in one day is $\frac{1}{9}$.

$\frac{1}{7}+\frac{1}{9}=\frac{1}{t}$

$\frac{9+7}{63}=\frac{1}{t}$

$\frac{16}{63}=\frac{1}{t}$

$16t=63$

$t=\frac{63}{16}=3.9375\approx 4$

Therefore both will paint the house completely in 4 days.