Question

the mean weight of a loaf of bread was found by sampling to be 455 g, with a standard deviation of 5 g. assuming a normal distribution, find the percent of loaves with weights that are: less than 450 g, and greater than 445 g

Answer 1

One standard deviation is 68.2689492% of the total, and two standard deviations is 95.4499736%. the difference is 27.1810244%. Of course, this is the percent between one and two standard deviations away. Your question asks, essentially, for the percent between one and two deviations away on ONE side, so we need half of this, or 13.5905122%. 13.6% will probably suffice.