it john 4 hours to mow a lawn it takes maria 3 hours to mow the same lawn, how long would it take if they worked together?

Answer 1

well, if they mowed for 12 hours, they would cut 3+4=7 lawns.

rate=7lawns/12 hours

1lawn=rate*time=7/12 lawns/hr*time

time= 12/7 hrs or 1 5/7 hr

Answer 2

John mows lawn in 4 hrs or .25 lawn in 1 hr. Maria mows lawn in 3 hrs or .333 lawn in 1 hr. So in one hour they (combined) mow .25 + .333= .583 lawn(assuming they don't remow each others sections, lol)
1/.583 is 1.715hr
John should just go home and let maria do it all.