Question 1031529
Let {{{ x }}} = the number of cars he sold
Let {{{ y }}} = the number of cars remaining
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(1) {{{ 89*( x + y ) }}} = cost of all the cars he bought
(2) {{{ 225x - 89*( x + y ) = 2327 }}} profit after selling {{{ x }}} cars
(3) {{{ x + y <= 50 }}}
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(2) {{{ 225x - 89x - 89y = 2327 }}}
(2) {{{ 136x - 89y = 2327 }}}
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I think I got this by trial and error
First, I divided {{{ 2327 / 136 = 17.1 }}}
so, {{{ x }}} must be at least {{{ 17 }}}
Then I tried different value for {{{ x }}}
{{{ x = 23 }}}
{{{ 23*136 = 3128 }}}
{{{ 89y = 3128 - 2327 }}}
{{{ 89y = 801 }}}
{{{ y = 9 }}}
9 cars remain
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check:
{{{ x + y = 23 + 9 }}}
{{{ x + y = 32 }}}
(2) {{{ 225x - 89*( x + y ) = 2327 }}}
(2) {{{ 225*23 - 89*32 = 2327 }}}
(2) {{{ 5175 - 2848 = 2327 }}}
(2) {{{ 2327 = 2327 }}}
OK
Maybe there is a systematic way to 
get the answer -I don't know what it is.
Hope this helps