Question 1 - A-Level Maths

Exam Board	Edexcel
Module	S1 (Statistics 1)
Topic	Measures of Location and Spread
Type	Coding to simplify calculation

Using the coding \(y = \frac { x - 90 } { 5 }\), and showing each step in your working clearly, calculate the mean and the standard deviation of the 20 observations of a variable \(X\) given by the following table:

\(x\)	75	80	85	90	95	100	105	110
Frequency	1	2	3	6	4	2	1	1