Jack can do a job in 2 hours, Tom in 5.
Can someone verify the answer isn't one of the choices?

At vero eos et accusamus et iusto odio dignissimos ducimus qui blanditiis praesentium voluptatum deleniti atque corrupti quos dolores et quas molestias excepturi sint occaecati cupiditate non provident, similique sunt in culpa qui officia deserunt mollitia animi, id est laborum et dolorum fuga.
Et harum quidem rerum facilis est et expedita distinctio. Nam libero tempore, cum soluta nobis est eligendi optio cumque nihil impedit quo minus id quod maxime placeat facere possimus, omnis voluptas assumenda est, omnis dolor repellendus.
Itaque earum rerum hic tenetur a sapiente delectus, ut aut reiciendis voluptatibus maiores alias consequatur aut perferendis doloribus asperiores repellat.

Get our expert's

answer on brainly

SEE EXPERT ANSWER

Get your **free** account and access **expert** answers to this

and **thousands** of other questions.

- anonymous

Jack can do a job in 2 hours, Tom in 5.
Can someone verify the answer isn't one of the choices?

- katieb

I got my questions answered at brainly.com in under 10 minutes. Go to brainly.com now for free help!

Get this expert

answer on brainly

SEE EXPERT ANSWER

Get your **free** account and access **expert** answers to this

and **thousands** of other questions

- anonymous

##### 1 Attachment

- anonymous

x x
-- + -- = 1
2 5
Multiply every term by 10
5x + 2x = 10
7x = 10
x = 10/7
x = 1 and 3/7 of an hour.

- anonymous

but 7 isnt a common denominator?

Looking for something else?

Not the answer you are looking for? Search for more explanations.

## More answers

- anonymous

@Blexting - could you explain? this isn't AOPS where everyone understands.

- anonymous

isn't 1/2 + 1/5 = 3/10?

- anonymous

i mean 7/10 oops

- anonymous

OHH i see what i did wrong

- anonymous

i simplified but forgot to use the reciprocal denominator :P damnit

- anonymous

sorry, & thanks

- anonymous

x is the number of hours someone works.
Take Tom... in 1 hour he has done 1/5 of the job.. in 2 hours he has done 2/5 of the job... in 3 hours 3/5 of the job.
We want the job to add to 1 because then you have done "let's say 5/5" of the job which is the whole job.
in 1 hour jack would do 1/2 of the job and Tom 1/5 of the job. which would be 7/10 of the job.
in 2 hours jack would do 2/2 of the job and Tom 2/5 of the job.. which would be 1 2/5.. (Jack would have completed it on his own).
These are always setup the same way
x over (how long it takes for one person) + x over (how long it takes for the other person) = 1

- anonymous

Hrm. Never saw it that way. I just always thought of it through rates, and then just brute forced it. qq

- amistre64

1/2 + 1/5 = 7/10
7 parts get done in 1 hour, and there are a total of 10 parts to do.
after 1 hour, there are still 3 parts to finish up.
60 minutes/7 times 3 = how many minutes?

- amistre64

180/7 = 25.7 is close...
1 hour 25 minutes and a few seconds...

- anonymous

I left it 1 3/7 hours because it matched the multiple choice he was picking from.

- amistre64

thats a good option as well :)

Looking for something else?

Not the answer you are looking for? Search for more explanations.