Let the weight of box of biscuits :
The probability that the box is underweight is approximately
Bob measured the heights of 63 students. After analysis, he conjectured that the height, H, of the students could be modelled by a normal distribution with mean 166.5 cm and standard deviation 5 cm.
Later Bob noticed that the tape he had used to measure the heights was faulty as it started at the 5 cm mark and not at the zero mark.
What are the correct values of the mean and variance of the distribution of the heights of these students?