Question

The data base regarding the billing rates of K-Electric in lower earning areas of the Karachi shows the average billing for the electricity is normally distributed with an average of Rs.1100 with a standard deviation of Rs.100. If the bills are measured to the nearest Rs.50 find the probability that the next bill will contain                                                                                  

1. Below Rs.1090
2. Exactly Rs.1120
3. At least Rs.1110
4. Between 1270 and 1350 inclusive
5. Find the highest value of x having 15% of the bills having amount below that

Answer 1