Question

Item2

Answer 1

Answer:

Kindly check explanation

Step-by-step explanation:

Sample 1 :

Mean = (79.2 + 78.8 + 80 + 78.4 + 81) / 5 = 79.48

Range = 81 - 78.4 = 2.6

Sample 2 :

Mean = (80.5 + 78.7 + 81 + 80.4 + 80.1) / 5 = 80.14

Range = 81 - 78.7 = 2.3

Sample 3 :

Mean = (79.6 + 79.6 + 80.4 + 80.3 + 80.8) / 5 = 80.14

Range = 80.8 - 79.6 = 1.2

Sample 4 :

Mean =(78.9 + 79.4 + 79.7 + 79.4 + 80.6)/5 = 79.6

Range = 80.6 - 78.9 = 1.7

Sample 5 :

Mean = (80.5 + 79.6 + 80.4 + 80.8 + 78.8)/5 = 80.02

Range = 80.8 - 78.8 = 2

Sample 6 :

Mean =(79.7 + 80.6 + 80.5 + 80 + 81.1)/5 = 80.38

Range = 81.1 - 79.7 = 1.4

Xbar = mean of the means

Xbar = (79.48+80.14+80.14+79.6+80.02+80.38) / 6 = 79.96

Rbar = Mean of the sample ranges

Rbar = (2.6 + 2.3 + 1.2 + 1.7 + 2 + 1.4) / 6 = 1.87

n =5 ;D4 = 2.11 ; D3 = 0

From table, D4 = 2.11 ; D3 = 0

Range chart :

Upper Control limit, UCL = D4 * Rbar ; 2.11*1.87 = 3.9457 = 3.95

Lower Control limit, LCL = D3 * Rbar ; 0*1.87 = 0

Mean chart :

Xbar ± A2 * Rbar

From the table :

n = 5 ; A2 = 0.58

Lower control limit(LCL) = Xbar - A2*Rbar

LCL = 79.96 - (0.58*1.87) = 78.8754 = 78.88

Upper Control Limit (UCL) = Xbar + A2*Rbar

UCL = 79.96 + (0.58*1.87) = 81.0446 = 81.04

(78.88 ; 81.04)

The value of Each sample mean falls within the mean interval, Hence, We can conclude that process is on control.