Posted by sandra on Saturday, December 18, 2010 at 6:26pm.
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
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.
Related Questions
Math - Mike can mow a lawn in 3 hours. Paul can mow the same lawn in 2 hours. ...
algebra - Jack usually mows his lawn in 6 hours. Marilyn can mow the same lawn ...
algebra - Bob mosw his lawn in 3 hours, Jane can mow the same lawn in 5 hours. ...
smith - tom can mow a lawn in 4 hours. perry can mow the same lawn in 5 hours. ...
algebra - jack usually mows his lawn in 4 hours mariltn can mow the same yard in...
Algebra - Jack usually mows his lawn in 4 hours. Marilyn can mow the same yard ...
math - Jack usually mows his lawn in 4 hours. Marilyn can mow the same in 5 ...
alegbra - Jack usually mows his lawn in 4 hours. Marilyn can mow the same yard ...
math/117 - Jack usually mowes his lawn in 7 hours. Marilyn can mow the same yard...
Math - Jack usually mows his lawn in three hours. Marilyn can mow the same yard ...
For Further Reading
