Example 12:37 The mean wcight of 500 male students at a certain coilege is 151 lbs. and the standard deviation is 15 Ibs. Assuming that the weights are normally distributed, find how many students weight (i) between 120 and 155 lbs., (ii) more tban 155 lbs. [Given D(0.27) = 0.6064 and (2.07) the area under standard normal curve to the left of the ordinate at 1.] = 0.9808, where O (t) denotes
