There are 10 cars parked in a mall’s parking lot, each with the same number of customers inside. Each customer only makes 1 purchase. If the sports store makes 20 sales and the music store makes 30 sales, how many customers are in each of the cars?
As each sale represents a customer, there must be a total of 20 sports store sales + 30 music store sales = 
<gadget id="calculator">20+30</gadget>
<output>50</output>
50 customers.
There is an equal number of customers in every car, so there must be 50 total customers / 10 cars = 
<gadget id="calculator">50/10</gadget>
<output>5</output>
5 customers in each car.

<result>5</result>