Question

In a normal distribution, *about* 95% of the observations occur...

Within 1.5 standard deviations above and below the mean.

Within 1 standard deviation above and below the mean.

Within 2.96 standard deviations above and below the mean.

Within 3 standard deviations above and below the mean.

Within 2 standard deviations above and below the mean.

Answer 1

we know that in a normal distribution curve, 68% of the data is distributed within one stadndad deviation from the mean, 95% of the data is distributed within two stadndad deviation from the mean and 99.97% of the data is distributed within three stadndad deviation from the mean.

So, the question is asking us for the 95%

thus, we can say that "about 95% of the observation occur within 2 standard deviation above and below the mean"

So, option E is correct answer

option A, B, C and D are incorrect because these are providing incorrect values of standard deviation above and mean for 95% of the observation.