# Question

A commuter must pass through five traffic lights on her way to work and will have to stop at each one that is red. After keeping a record for several months, she developed the following probability model for the number of red lights she hits:

a) How many red lights should she expect to hit each day?

b) What’s the standard deviation?

a) How many red lights should she expect to hit each day?

b) What’s the standard deviation?

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