Question

Working alone it takes Ryan 13.4 weeks to build a home.Jack can build the same home in 13.1 weeks how long would it take them if they work together

Answer 1

Answer: 6.62 weeks

Explanation:

Time taken by Ryan to build a home = 13.4 weeks

Time taken by Jack to build the same home = 13.1 weeks

Let t be the time to complete a house if they work together, then

`(1)/(t)=(1)/(t)`=
`\frac{1}{\text{time taken by Ryan alone}}+\frac{1}{\text{time taken by Jack alone}}`

`=(1)/(13.4)+(1)/(13.1)\\\\=(13.1+13.4)/(175.54)\\\\=(26.5)/(175.54)`

`\\\Rightarrow\ t=(175.54)/(26.5)\\\Rightarrow\ t=6.62\ weeks`