Ex 13.2, 10 - Chapter 13 Class 11 Statistics
Last updated at April 16, 2024 by Teachoo
Last updated at April 16, 2024 by Teachoo
Ex 13.2, 10 The diameters of circles (in mm) drawn in a design are given below: h = class size = 36.5 − 32.5 = 4 Mean(𝑥 ̅) = A + (∑▒𝑓𝑖𝑦𝑖)/(∑▒𝑓𝑖) ×ℎ = 42.5 + 25/100 ×4 = 42.5 + 1/4 ×4 = 43.5 Variance (𝜎)2 = ℎ2/N2 [𝑁∑▒𝑓𝑖𝑦𝑖2 − (∑▒𝑓𝑖𝑦𝑖)^2 ] = 42/1002 [100 × (199) – (25)2] = 16/10000 [19900 −625] = 16/10000 × 19275 = 30.84 ∴ Standard deviation (𝜎) = √Variance 𝜎 = √30.84 = 5.55