Question 912612
Let {{{ x }}} = the price of the most expensive book
The cost of the other 2 books is
{{{ 150 - x }}}
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Given:
{{{ x = 1.5*( 150 - x ) }}}
{{{ x = 225 - 1.5x }}}
{{{ 2.5x = 225 }}}
{{{ x = 90 }}}
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The most expensive book costs $90
check:
{{{ x = 1.5*( 150 - x ) }}}
{{{ 90 = 1.5*( 150 - 90 ) }}}
{{{ 90 = 1.5*60 }}}
{{{ 90 = 90 }}}
OK