Question

Joey can assemble all of his factory work in four hours. Phil takes six hours to assemble the same amount of factory work. If they worked together to assemble the same job together, how long would it take?

Answer 1

Mean time :
`\frac{4+6}2=5`

Since they're two, it would take
`\frac{5}2=\boxed{2.5\text{ hours}}`