Question

B demora el doble de lo que A tarda en realizar un trabajo. Juntos, terminan el trabajo en 4 horas. ¿Cuánto tiempo empleará B en efectuar separadamente dicho trabajo?

Answer 1

For this case we define the following variable:

x: time it takes A to perform the job separately.

We then have the following equation:

`(1)/(x) + (1)/(2x) = (1)/(4)`

From here, we clear the value of x.

We have then:

`(4x)/(x) + (4x)/(2x) = (4x)/(4)`

`4 + 2 = x`

`x = 6`

Therefore, the time it takes for B to complete the work is:

`2x = 2 (6) = 12`

Answer:

B will spend 12 hours doing that work separately