One of the first topics that many Secondary 4 E-Math students learnt is a statistics chapter known as **Mean and Standard Deviation** (SD for short).

The nice thing about this chapter is that the 2 most important formula are both available in the E-Math (subject code: 4016) formula sheet! No memorization required, just understanding of their usage.

In this post, I will illustrate 2 methods to get the answers for mean and SD for ungrouped data (refer to example). The 2 methods are **manual** and **calculator**.

**Example:**

Given 15, 6, 18, 9, 2 and 4, find the mean and standard deviation.

**Manual:**

**Calculator, Casio fx-85MS:**

- Mode, 2(SD)
- Enter the data in this manner
**,**15, M+ **To get mean:**Press 'Shift', 2, 1,=**To get SD:**Press 'Shift', 2, 2,=

Here are some additional information you can obtain using the calculator:

Answers obtained through both methods are the same. By knowing these 2 methods, you can use either to double check.

steve okpachu says

thank you for registering me. i love maths and want to improve my knowledge of o level maths.

kind regards,

steve okpachu