Edu-Spot covering the three methods of Mean, formula of Mode, and two formulas of Median
Three Methods to Find Mean (Average):
- Direct Method:
Mean =
(Used for ungrouped or small grouped data)
- Assumed Mean Method:
Mean= A+
Where A = assumed mean, d = x−A
- Step-Deviation Method:
Mean= A+
Where u=, and h = class width
📌 Formula for Mode (for grouped data):
Mode= l+
Where:
- l = lower boundary of modal class
- f1 = frequency of modal class
- f0 = frequency before modal class
- f2 = frequency after modal class
- h= class width
📈 Two Formulas of Median (Grouped Data):
Even & Odd Formula
✅ Step 1: Arrange the data in ascending order.
🔢 If the number of values (n) is ODD:
Use the formula:
Median=Value at position ()
🔢 If the number of values (n) is EVEN:
Use the formula:
Median= ()
- For Continuous Frequency Table:
Median= l+ ( X h
Where:
- l = lower boundary of median class
- F = cumulative frequency before median class
- f = frequency of median class
- h = class width
- Empirical Relationship Formula (if mode and mean are known):
3 Median = 2Mean + Mode