SOLUTION: If it takes 6 men 4 days to dig a hole 3 metres deep, how long will it take for 10 men to dig a hole 7 metres deep?

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Question 1144061: If it takes 6 men 4 days to dig a hole 3 metres deep, how long will it take for 10 men to dig a hole 7 metres deep?
Found 2 solutions by josgarithmetic, ikleyn:
Answer by josgarithmetic(39614) About Me  (Show Source):
You can put this solution on YOUR website!
r, the one-man digging rate
system%28%286r%294=3%2C%2810r%29%2Ax=7%29

%2810r%2Ax%29%2F%286%2A4%2Ar%29=7%2F3

%2810%2F%286%2A4%29%29x=7%2F3

%2810%2F%282%2A3%2A4%29%29x=7%2F3

%285%2F4%29x=7

x=28%2F5
x=5%263%2F5

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(number seems strange. Look for any mistakes in steps.)

Answer by ikleyn(52756) About Me  (Show Source):
You can put this solution on YOUR website!
.

From the first statement, the rate of work is  3%2F%286%2A4%29 = 1%2F%282%2A4%29 = 1%2F8 meter per one man per day.


Let the number of days is x.  Then the equation to find the unknown x is


    %281%2F8%29%2A10%2Ax = 7,


which gives


    x = %287%2A8%29%2F10 = 56%2F10 = 56%2F10 days = 53%2F5 days = 5.6 days.    ANSWER


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Be aware (!) :   writing by @josgarithmetic is   WRONG  and  INCORRECT   from the first line to the end.

For your safety,  ignore his post.