Answer:
Variance = 9
Standard deviation = 3
Step-by-step explanation:
Step 1
Find the Mean
Means = Sum of values/Number of values
= 0 + 1 + 4 + 4 + 6 + 7 + 7 + 7 + 9/9
= 45/9
= 5
Step 2
The formula for Sample variance
= (x - Mean)²/n - 1
Where
n = number of values = 9
Hence:
Sample variance =
( (0 - 5)² + (1 - 5)²+ (4 - 5)² + (4 - 5)² + (6 - 5)² + (7 - 5)² + (7 - 5)² + (7 - 5)² + (9 - 5)²)/9 - 1
= (-5² + -4²+ -1² + -1² + 1² + 2² + 2² + 2² + 4²) /8
= (25 + 16 + 1 + 1 + 1 + 4 + 4 + 4 + 16)/8
= 72/8
= 9
Sample Standard deviation = √Sample variance
= √9
= 3
