Answer the following question, with explanation first.
At a bus station, a bus leaves every half-hour for 12 hours a day. How many buses leave the station for 5 days?

120
If one bus leaves every half - hour, then during one hour, there are 1 + 1 = 2 buses that leave the station.

During 5 days 2 * 12 * 5 = 120 buses leave the station.

.

So, the answer is 120