Given:
Size of lot (N)=1900
Sample Size (n) =125
Acceptance Number (c)=2
Proportion defective (p) can be calculated as :
For np=1.8,
`p=1.8/125=0.0144`
For np=4.2,
`p=4.2/125=0.0336`
For np=6.0,
`p=6.0/125=0.048`
So these values of p completes the Column 1 for p.
Now column 2 can be obtained by multiplying p values with 100.
Now let's fill the column 3 (np) values,
For p=0.0016,
`np=125*0.0016=0.2`
For p=0.008,
`np=125*0.008=1`
For p=0.012,
`np=125*0.012=1.5`
For p=0.0224,
`np=125*0.0224=2.8`
For p=0.0416,
`np=125*0.0416=5.2`
...
Given:
Size of lot (N)=1900
Sample Size (n) =125
Acceptance Number (c)=2
Proportion defective (p) can be calculated as :
For np=1.8,
`p=1.8/125=0.0144`
For np=4.2,
`p=4.2/125=0.0336`
For np=6.0,
`p=6.0/125=0.048`
So these values of p completes the Column 1 for p.
Now column 2 can be obtained by multiplying p values with 100.
Now let's fill the column 3 (np) values,
For p=0.0016,
`np=125*0.0016=0.2`
For p=0.008,
`np=125*0.008=1`
For p=0.012,
`np=125*0.012=1.5`
For p=0.0224,
`np=125*0.0224=2.8`
For p=0.0416,
`np=125*0.0416=5.2`
For p=0.0512,
`np=125*0.0512=6.4`
Now let's calculate the Probability of acceptance by the cumulative Poisson formula,
`P_a=sum_(x=0)^c(e^(-np)(np)^x)/(x!)`
We have to calculate P_a for each value of p,
For p=0.016
`P_a=P_0+P_1+P_2`
`=(e^(-0.2)(0.2)^0)/(0!)+(e^(-0.2)(0.2)^1)/(1!)+(e^(-0.2)(0.2)^2)/(2!)`
`=0.818730753+0.163746151+0.016374615`
`=0.998851519`
`=~~0.999`
For p=0.008,
`P_a=(e^(-1)(1)^0)/(0!)+(e^(-1)(1)^1)/(1!)+(e^(-1)(1)^2)/(2!)`
`=0.367879441+0.367879441+0.183939721`
`=0.919698603`
`=~~0.92`
For p=0.012,
`P_a=(e^(-1.5)(1.5)^0)/(0!)+(e^(-1.5)(1.5)^1)/(1!)+(e^(-1.5)(1.5)^2)/(2!)`
`=0.22313016+0.33469524+0.25102143`
`=0.808846831`
`=~~0.809`
Similarly we can calculate P_a for all values of p, which are shown in the attached image.
Now let' calculate AOQ,
`AOQ=(P_a*p)(N-n)/N`
If `n/N<=0.1`
Then, AOQ `=P_a*p`
Now let's calculate AOQ,
For p=0.0016,
`AOQ=0.0016*0.999=0.0015984`
For p=0.008,
`AOQ=0.008*0.92=0.00736`
Similarly we can calculate AOQ, for other values of p.
Please refer to the attached image, where all calculations are shown.
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