One bag of popcorn would cost $6.50
To solve this, we can set up equations:
28p+40c=$282
17p+20c=$160.50
To solve this system, we would need to make either the candy bars the same or the bags of popcorn the same. Since we are solving for bags of popcorn, we will make the candy bars the same:
20(28p+40c=$282)
40(17p+20c=$160.50)
Which would give you:
560p+800c=$5,640
680p+800c=$6,420
Subtract them:
(680p+800c=$6,420)
-(560p+800c=$5,640)
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120p=$780
Now divide by 120 to get the price of one bag of popcorn:
120p=$780
_________
120
p=$6.50