Sarah can weed a garden in two hours. Max can weed the same garden in 3 hours. At this rate, how long would it take them to weed the garden working together, but independently?
I know the answer, do you?
2007-08-27 00:08:29 · 17 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
72 minutes, based on my understanding. But I'm kinda doubtful about the "but independently" clause. How can they work together independently?
2007-08-27 00:14:17 · answer #1 · answered by Ash Dy 2 · 1⤊ 0⤋
Sarah's rate = 1/2 garden per hour
Max' rate = 1/3 garden per hour.
Together rate = (1/2 + 1/3) garden per hour
= 5/6 garden per hour.
Time taken by them weeding together but independently = 1/rate
= 1/(5/6 per hour)
= 6/5 hour
= 1 hour 12 minutes.
2007-08-27 00:17:31 · answer #2 · answered by sv 7 · 1⤊ 0⤋
The combined rate of doing the work (by both max +sarah)would be faster than Sarah 's two hour rate
So to complete the job to weed the garden together would take 1.2 hours. or one hour and 12 minutes.
2007-08-27 00:54:37 · answer #3 · answered by goring 6 · 0⤊ 0⤋
'Rate' is the key word in this kind of question.
Sarah's rate is 0.5 'gardens' per hour and Max's rate is 0.33 'gardens' per hour, so together they can weed 0.83 'gardens' per hour (that is 1/2 + 1/3 = 5/6). Thus, working together, they will take 6/5 hrs, or 1h12m to weed one 'garden'.
2007-08-27 00:18:46 · answer #4 · answered by Anonymous · 1⤊ 0⤋
1/2x + 1/3x = 1
Multiply both sides of the equatio by 6
6(1/2x) + 6(1/3x) = 6(1)
3x + 2x = 6
Collect like terms
5x = 6
Divide both sides of the equation by 5
5x / 5 = 6/5
x = 6/5
x = 1 1/5
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Find minutes
There are 60 minutes in one hour
Multiply 1/5 times 60
1/5(60) =
60/5 = 12 Minutes
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Working together, Sarah and Max will weed the garden in 1 hour and 12 minutes.
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2007-08-27 01:55:22 · answer #5 · answered by SAMUEL D 7 · 0⤊ 0⤋
It's really poor that out of so many answers only two so far were right: It is 1.2 hours, which is 1h 12min = 72 min
The way to calculate it is either: 1/ (1/2 + 1/3)
or 2 * 3 / (2+3)
The clause independently means that the work as if they were alone - and they will not chat, but work.
2007-08-27 00:23:58 · answer #6 · answered by Ernst S 5 · 1⤊ 0⤋
Let x = no. of hours to finish the job.
Equation:
x/3 + x/2 = 1
2x/6 + 3x/6 = 1
5x/6 = 1
5x = 6
x = 1 1/5
Answer: 1 1/5 hr or 1 hour and 12 minutes
2007-08-27 00:24:48 · answer #7 · answered by Jun Agruda 7 · 4⤊ 0⤋
Who cares as long as they get the job done. By the way when they get done over there send Sara & Max to weed my Garden,they won't have to figure out who weeds faster or finishes first. Sheeees
2007-08-27 00:13:21 · answer #8 · answered by CJ 3 · 0⤊ 1⤋
It should be 2.5 hours but it depends if they are doing an equal amount of the garden each.
2007-08-27 00:14:23 · answer #9 · answered by barbedwireribbons 3 · 0⤊ 1⤋
1.2? hours
how can it be 2.5 hours when she can weed a garden in 2 hours maby
2007-08-27 00:13:43 · answer #10 · answered by Anonymous · 0⤊ 1⤋