A restaurant manager states the number of customers that enter the
restaurant is equal to 3 times the number of people that buy a hotdog from
the hotdog cart plus 15.
The manager also states that the number of customers that enter their
restaurant is equal to 2 times the number of people that buy a hotdog from
the hotdog cart plus 60.
What number of people buying a hotdog from the hotdog cart across the
street makes the equation 3x +15 = 2x +60 true?