Calculating probality of wrong prescription where n > 30 as shown in the example

[otuomasp]

The probability that a doctor gives the wrong prescription to a patient is 0.005. During the month of March 2015, a given doctor attended to 600 patients.Determine the mean and standard deviation for the distribution.
What is the probability that the doctor gave more than three wrong prescriptions during the month of March 2015?

 

[Harry_the_cat]

The probability that a doctor gives the wrong prescription to a patient is 0.005. During the month of March 2015, a given doctor attended to 600 patients.Determine the mean and standard deviation for the distribution.
What is the probability that the doctor gave more than three wrong prescriptions during the month of March 2015?

This is an example where you can use the "normal approximation to the binomial distribution" because n is large. Have you learnt about that yet?