Salim sells fax machines that come in Standard and Enhanced models. The Standard model sells for $325 and the Enhanced model sells for $385. If Salim sold a total of 35 units and took in $12,575, how many of the Enhanced model did he sell?

Answer 1

number of standard models --- x
number of enhanced models --- 35-x

solve for x

325x + 385(35-x) = 12575

Answer 2

325x + 385(385 - x)= 12575
-325x + 13,475 - 385x = 12575
- 13,475 -325 = -13475

60x = 900
60x/60 = 900/60
x = 15