Simpangan baku dari 7, 11, 13, 9, 15 adalah

jawab

xi = 7, 11, 13, 9 , 15
n = 5
∑xi= 7 + 11 + 13 + 9 + 15 = 55
X rata = 55/5 = 11

simpangan baku = s = √ S²
S²= ∑ (xi - x)² / (n)

S² = { (11-7)² + (11-11)² +(13-11)² +(9-11)² +(9-15)²} / (5)
s² = ( 16 +0 +4 + 4+ 36) / (5) 
S² = 60/5
s² = 12

simpangan baku  s = √s² = √12 = 2√3