Question

Shane can shovel the driveway in 4 hours, but if his sister helps it would take 2 hours. How long would it take Taylor to shovel the driveway alone

Answer 1

Answer: 4 hours

Explanation:

Shane:
`(1)/(4)\ \text{job per hour}`

Taylor:
`(1)/(x)\ \text{job per hour}`

Together:
`(1)/(2)\ \text{job per hour}`

Shane + Taylor = Together

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

`(8x)(1)/(4)` +
`(8x)(1)/(x)` =
`(8x)(1)/(2)`

2x + 8 = 4x

8 = 2x

4 = x