If it takes Jack 6 hours to mow the lawn and Mary 7 hours How long will it take if they mow the lawn together?

Answer 1

It stands to reason that if you have 2 people performing the labor normally performed by one, it will take half the time. Jack takes 3 hours to mow half the lawn and Mary takes 3.5 hours to mow half the lawn. Average the two (because Jack will mow more lawn than Mary will) and it will take 3.25 hours for Jack and Mary to mow the lawn together.

1. well, theres double the help, so 6 divided by 2 equals 3. and 7 divided by 2 equals 3 1/2 So, 3+3 1/2= 6 1/2 hours.
2. Or, if this is a trick question, Jack can mow the front lawn, while Mary mows the back lawn, it would take 7 hours. because, Jack mows the lawn, but the time still goes on, because Marys not finished, and it says "It takes MAry 7 hours".
3. OR another answer to a trick question, JAck could be mowing the lawn, but, Marycould be with him. not mowing, just along his side. so it would take 6 hours. or vice-versa.
4. or, a mathematical point again, 6+7=13 divided by 2 (two people) equals again, 6 1/2 hours.

In Conclusion:

MATHEMATICAL ANSWER: TRICK QUESTION ANSWER:

6 1/2 Hours Theory 2 or 3

hope i helped.