jack mows his yard in 4hr. sue mows in 3hr. how long will it take both of them to mow the same yard?
2hr?

Question

jack mows his yard in 4hr. sue mows in 3hr. how long will it take both of them to mow the same yard?
2hr?

slaaibak · Answer

IIRC, it's something like

1/3 + 1/4 = 1/(new rate) = 7/12

Therefore, answer is 12/7 hours.

Not sure tho :/

anonymous · Answer

i dont think my answer is correct im still working on it, its confusing

slaaibak · Answer

I think my answer is, it makes logically sense.

It would definately be less than 2 hours, since sue mows faster than jack.

similarly, it would definately be less than 1.5, since jack mows longer than 2 hours.

$$1.5 < {12 \over 7} < 2$$

Therefore my answer and method is correct.

It takes them both 12/7 hours.

slaaibak · Answer

*similarly, it would definately be MORE than 1.5, since jack mows longer than sue. Sorry,typo*

hero · Answer

$$\frac{a \times b}{a + b}$$

hero · Answer

$$\frac{4 \times 3}{4 + 3} = \frac{12}{7}$$