be about...?
a. .40
b. .45
c. .49
d. none of these
2006-10-28 10:42:45 · 2 answers · asked by mrkittypong 5 in Science & Mathematics ➔ Engineering
2 standard deviations on either side of the mean has an area of 0.95, which must be 0.475 above the mean and 0.475 below. Answers A and B are therefore obviously too small. Choose between C and D.
2006-10-28 10:50:43 · answer #1 · answered by Anonymous · 0⤊ 1⤋
go to a tables book and look up z score for the normal distribution. It will have a whole lot of values from 1.0000 to 0.0000. If you cant be bothered doing that go into excel and type function: =normsdist(2.575) this will return a value 0.994988 which means 99.4988% is less than 2.575 stdev. So to the mean would be 50% less eg 49.4988 so depending on how pedantic you want to be it could roughly be C but id be happy to defend d none of these
2006-10-29 05:36:05 · answer #2 · answered by cmsrmt 2 · 0⤊ 0⤋