Question 987556
For last year, 1 plough would take 3
times as long, or:
1 plough plows a field in 51 hrs
51 ploughs plow a field in 1 hr
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You only need 1/5 as many ploughs if
you want to take 5 times as long, so
{{{ 51/5 }}} plows plough the field in {{{ 5 }}} hrs
{{{ 10 }}} plows won't quite do it, they will
take {{{ 5.1 }}} hrs, so {{{ 11 }}} ploughs are needed