WILL STAR & FAN! Martha can rake the leaves i her yard in 2 hours. Her younger brother can do the job in 6 hours. How long will it take them to the job if they worked together? I know the answer is 3/2 but i dont really understand how this answer was gotten
So the problem says Martha rakes the leaves in 2 hours, and her younger brother does it in 6.
You want to see the amount of time it takes if they both raked leaves at the same time
yes
her brother takes 3 times longer than Martha to rake the leaves.
so if M equals Martha, 3M=M
both added together is 8 so i retriceued dividing by 2 lol
oops, not 3M equals M. 3M equals her brother
but i catch your drift so 2*3=6
wait, now im messing up, hold on, I'll rewrite it
take your time :)
sorry, the post button disappeared for some reason
Martha takes 2 hours Her brother takes 6 hours Lets say Martha equals M and her brother equals B
great, im making it too complex now
lmao im a lil confused. but how does the answer end up being 3/2 hours then?
how did you get 3/2?
my brain isn't working right now...
Got it! martha takes 2 hours, so in 1 hour she rakes 1/2 of the leaves
her brother takes 6 hours, so in 1 hour her brother rakes 1/6 of the leaves
x/2 + x/6 = 1 x is hour
3/2 is the in the answer key
ok but what would have to be added together?
cause 1/2 + 1/6 is 2/3 not 3/2 thats one of the answer choices to trick me tho
theres a few steps before that, its not simple addition
basically, x/2 + x/6 equals (1/2 + 1/6) times X
so that would make it (1/2 + 1/6) * X = 1
so 2/3 times x = 1
ohhhhh ok. so when you divide 1 by a fraction you flip it?
you basically solve for x after that, since X is the amount of time it took to rake the leaves
thanks :) got it
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