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This should be simple...

18 workers took 12 days to dig a 60m long canal. How many workers would it take to dig a canal of length 95m in 9 days? (assume same width of canal..)

What I tried:
I thought of it in terms of total "power" depending proportionally on number of workers so
P=kN
so from info given 60/12=18k ---> k=5/18

We need "power" of 95m/9d so
95m/9d = 5N/18 which gives N= 38
Is this correct?
I assumed the power is proportional to number of workers although the question didn't explicitly state it. I don't think there's any other way to solve the question with the info given and from the context where I found the question I think we are expected to make the simplification.
I feel like I complicated it with the weird power so if anyone can present it so it's simpler I'd appreciate it.
Original post by monk1324
18 workers took 12 days to dig a 60m long canal. How many workers would it take to dig a canal of length 95m in 9 days? (assume same width of canal..)

What I tried:
I thought of it in terms of total "power" depending proportionally on number of workers so
P=kN
so from info given 60/12=18k ---> k=5/18

We need "power" of 95m/9d so
95m/9d = 5N/18 which gives N= 38
Is this correct?
I assumed the power is proportional to number of workers although the question didn't explicitly state it. I don't think there's any other way to solve the question with the info given and from the context where I found the question I think we are expected to make the simplification.
I feel like I complicated it with the weird power so if anyone can present it so it's simpler I'd appreciate it.


I think how I'd approach it is exactly the same-ish.

18 workers put in work for 12 days to make 60m. So 18 * 12 'worker days' were put in. (216)

These 216 worker days created a 60m long canal. We could assume that something 95/60 times longer would take 95/60 more time, which would be 342 'worker days'.

Given that it has to take 9 days, it would take 342/9 = 38 workers.

I doubt that this answers your question but.. I dunno, confirms that you are right, I suppose (provided the assumptios are good).
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Notnek
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Original post by monk1324
18 workers took 12 days to dig a 60m long canal. How many workers would it take to dig a canal of length 95m in 9 days? (assume same width of canal..)

What I tried:
I thought of it in terms of total "power" depending proportionally on number of workers so
P=kN
so from info given 60/12=18k ---> k=5/18

We need "power" of 95m/9d so
95m/9d = 5N/18 which gives N= 38
Is this correct?
I assumed the power is proportional to number of workers although the question didn't explicitly state it. I don't think there's any other way to solve the question with the info given and from the context where I found the question I think we are expected to make the simplification.
I feel like I complicated it with the weird power so if anyone can present it so it's simpler I'd appreciate it.

Your way seems fine to me but I'll give you a simpler way to think about it:

9 days instead of 12 days will require 12/9 times the number of workers since fewer days means more workers.

95m intead of 60m will require 95/60 times the number of workers to build a longer canal.

18 x (12/9) x (95/60) = 38

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