Answer:
$81
Step-by-step explanation:
We have:
20x (20 dollars per ski lesson)
60y (60 dollars per lift pass)
70z (70 dollars for ski lesson and pass)
We are given:
42 lift tickets sold
23 lessons sold
50 people bought 1 option
We need to find how many people bought both the ski lesson and pass:
42 + 23 = 65 things sold total
Only 50 people bought 1 item
65 - 50 = 15 people bought both ski lesson and pass
Now we find the total costs of everything combined:
70(15) + 60(34) + 60(16) = 4050
Mean: 4050/50 people = $81