Data are drawn from a symmetric and bell-shaped distribution with a mean of 120 and a standard deviation of 5. there are 900 observations in the data set.

What is the question?

This is an example of an ideal distribution and statical preview of the sample gathered from the population. 900 samples is a great number considering the central limit theorem of 30.
This distribution could also be described as a mesokurtic and normal form of the statistical model.

Statistics. Statistics is a branch of mathematics which is the scientific study of mathematical values pertaining to qualitative descriptions and transcribe them into quantifying values such as the descriptive statistics and infuses these quantities in the field of inferential statistics. In these two categories involve probabilities, distribution and deviations which are mainly compositions of the descriptive statistics. Inferential statistics will involve comparison and variation of the given values. Methods are t-test, analysis of variance, and two-way analysis of variance and other methods. 

8-2x+3x2=6 and six is your answer