
David W. answered 03/02/16
Tutor
4.7
(90)
Experienced Prof
Let x=number of Apples Sam bought
Translate:
"Sam bought some apples at 60c each" means spent = $0.60x
"sold all but 5 of them at $1.00 each" means earned = $1(x-5)
Math:
earned - spent = profit
$1.00(x-5) - $0.60x = $5.00
$1.00x - $5.00 - $0.60x = $5.00 [expand]
($1.00 - $0.60)x - $5.00 = $5.00 [combine terms]
$0.40x = $10.00 [add $5.00 to both sides]
x = 25 apples
Checking (very important):
Sam bought 25 apples for $0.60 each ($15.00) and sold all but 5 (that is, 20) at $1.00 each (total $20.00) and made a profit of $5.00 ($20.00 - $15.00 = $5.00) YES!