A restaurant is experiencing discontentment among its customers. It analyses that there are three factors responsible viz. food quality, service quality and interior décor. By conducting an analysis, it assesses the probabilities of discontentment with the three factors as 0.40, 0.35 and 0.25 respectively. By conducting a survey among the customers, it also evaluated the probabilities of a customer going away discontented on account of these factors as 0.6, 0.8 and 0.5, respectively. With this information, the restaurant wants to know that, if a customer is discontented, what are the probabilities that it is so due to food, service or interior décor?

Exponential Smoothing Method

From the following data compute quartile deviation and the coefficient of skewness:

Standard normal distribution:

 Statistics can prove anything’

‘Figures cannot lie’

Comment on the above two statements, indicating reasons for the existence of such divergent views regarding the nature and functions of statistics

Bayes' Theorem

Calculate the mean, median and mode from the following data relating to production of a steel mill for 60 days