Question 1078438
Let {{{ c }}} = number of chocolate bars
they had in the beginning
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Day 1
They sold {{{ (2/5)*c }}} leaving
{{{ (3/5)*c }}}
Day 2
They sold {{{ (1/2)*(3/5)*c = (3/10)*c }}}
leaving {{{ (3/10)*c }}} chocolate bars
Day 3
They sold {{{ (2/3)*(2/5)*c = (4/15)*c }}}
so there is {{{ (3/10)*c - (4/15)*c }}} left
{{{ (9/30)*c - (8/30)*c  = (1/30)*c }}}
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I am given that:
{{{ (1/30)*c = 50 }}}
{{{ c = 1500 }}}
They had 1,500 bars in the beginning
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check the answer:
They sold {{{ (2/5)*1500 = 600 }}} on day1
leaving {{{ 1500 - 600 = 900 }}} bars
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They sold {{{ (1/2)*900 = 450 }}}
leaving {{{ 450 }}} bars on day 2
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On day 3 they sold
{{{ (2/3)*600 = 400 }}} bars
{{{ 450 - 400 = 50 }}} bars
OK