A certain gas station offers regular and premium gas. Of the customers that usually stop for gas at this station, 60 % use regular gas. Of those using regular, they fill their tanks 50% of the time. Customer who use premium gas fill their tanks 30% of the time.

Draw a tree diagram displaying the various options for a customer who stops for gas.

What is the probability that a customer fills up their tank?

The next customer that stops for gas fill up their tank. What is the probability that they used premium?