Question 1095074
Let {{{ x }}} = total number of pages in book
The 1st day:
{{{ ( 2/7)*x }}}
( note there is {{{ 5/7 }}} of the book left to read )
The 2nd day:
{{{ (3/5)*(5/7)*x }}}
{{{ ( 3/7 )*x }}}
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I can say:
{{{ (2/7)*x + ( 3/7 )*x + 140 = x }}}
Multiply both sides by {{{ 7 }}}
{{{ 2x + 3x + 980 = 7x }}}
{{{ 2x = 980 }}}
{{{ x = 490 }}}
There are 490 pages in book
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check:
{{{ (2/7)*490 + (3/7)*490 + 140 = 490 }}}
{{{ 140 + 210 + 140 = 490 }}}
{{{ 490 = 490 }}}
OK