Suppose the Kwik-E-Mart has 3 Squishee machines, which, during a peak period, sees 90 customers per hour. Each customer uses a Squishee machine about 90 seconds on average. Assume that customer inter-arrival times and service times are exponentially distributed.

Assume that customers can line up in one long line, and take the next Squishee machine when its available.

What is the average amount of time a customer waits in line in seconds? Round to the nearest second