<PRE><B>Question 945774</B>
Working on the wall, you have:
60 men for 10 days
55 men for 10 days
50 men for 10 days
45 men for 10 days
40 men for 10 days
etc.
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60 men build 1 wall in 40 days
1 man builds 1/60 of a wall in 40 days
1 man builds 1/240 of a wall in 10 days
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60 men build {{{ 60/240 = 1/4 }}} of a wall in 10 days
55 men build {{{ 55/240 = 11/48 }}} of a wall in 10 days
50 men build {{{ 50/240 = 5/24 }}} of a wall in 10 days
45 men build {{{ 45/240 = 9/48 }}} of a wall in 10 days
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This sequence is:
{{{ 12/48 + 11/48 + 10/48 + 9/48 }}} etc.
{{{ ( 1/48 )*( 12 + 11 + 10 + 9 + 8 + 7 + 6 + 5 + 4 + 3 + 2 + 1 )
{{{ ( 1/48)*78 = 1.625 }}} walls
I want the time for just 1 wall
{{{ 12 + 11 + 10 + 9 + 8 = 50 }}} too much time
{{{ 12 + 11 + 10 + 9 = 42 }}} too little time
{{{ 42/48 + 6/48 }}} is the answer
{{{ ( 6/8 )*10 = 7.5 }}} days
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{{{ 10*4  = 40 }}} days
{{{ 40 + 7.5 = 47.5 }}}
My answer is 47.5 days to build the wall
This is while 40 men are working on it
Hope I got it

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