Question

It takes 54 minutes for 4 people to paint 6 walls. How many minuets does it take 6 people to paint 7 walls?

Answer 1

It takes 42 minutes for 6 people to paint 7 walls

Solution:

It takes 54 minutes for 4 people to paint 6 walls

To find: Minutes required for 6 people to paint 7 walls

If
`M_1` men can do
`W_1` work in
`D_1` days working
`H_1` hours per day and
`M_2` men can do
`W_2` work in
`D_2` days working
`H_2` hours per day, then

`(M_1D_1H_1)/(W_1) = (M_2D_2H_2)/(W_2)`

M = Number of men

D = Number of days

H = Number of hours per day

W = Amount of work

Here in this sum,

54 minutes for 4 people to paint 6 walls

`H_1 = 54 minutes ; M_1 = 4 people ; W_1 = 6 walls`

Minutes required for 6 people to paint 7 walls

`H_2 = ? ; M_2 = 6 people ; W_2 = 7 walls`

Substituting the values in formula, we get

`(54 * 4)/(6) = (H_2 * 6)/(7)\\\\9 * 4 = (H_2 * 6)/(7)\\\\H_2 = (36 * 7)/(6)\\\\H_2 = 42`

Thus it takes 42 minutes for 6 people to paint 7 walls