Question Help When purchasing bulk orders of​ batteries, a toy manufacturer uses this acceptance sampling​ plan: Randomly select and test 36 batteries and determine whether each is within specifications. The entire shipment is accepted if at most 2 batteries do not meet specifications. A shipment contains 3000 ​batteries, and 3​% of them do not meet specifications. What is the probability that this whole shipment will be​ accepted? Will almost all such shipments be​ accepted, or will many be​ rejected?

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Answer:

The probability is [tex]P(X  \le 2 ) = 0.9072[/tex]

The company will accept 90.72% of the shipment and will reject [tex](100 -90.72) =  9.2\%[/tex] of the shipment , so many of the shipment are rejected

Step-by-step explanation:

From the question we are told that

   The  sample size is  n =  36

   The  proportion that did not meet the requirement is  [tex]p =  0.03[/tex]

Generally the probability that the whole shipment is accepted is equivalent to the probability that there is at most 2 batteries that do not meet the requirement , this is mathematically represented as

     [tex]P(X  \le 2 ) = [ P(X =  0 ) +  P(X =  1 ) + P(X = 0)][/tex]

=>   [tex]P(X  \le 2 ) = [ [^{n}C_0 * (p)^{0} *(1-p)^{n-0} ] +  [^{n}C_1 * (p)^{1} *(1-p)^{n-1} ] +  [^{n}C_2 * (p)^{2} *(1-p)^{n-2} ]][/tex]

Here C stands for Combination (so we will be making the combination function in our  calculators )

So

=> [tex]P(X  \le 2 ) = [ [^{36}C_0 * (0.03)^{0} *(1-0.03)^{36-0} ] +  [^{36}C_1 * (0.03)^{1} *(1-0.03)^{36-1} ] +  [^{36}C_2 * (0.03)^{2} *(1-0.03)^{36-2} ]][/tex]

=> [tex]P(X  \le 2 ) = [ [1 * 1 * 0.3340  ] +  [36* 0.03 *0.3444 ] +  [630 * 0.0009 *(0.355 ]][/tex]

=>[tex]P(X  \le 2 ) = 0.9072[/tex]

The company will accept 90.72% of the shipment and will reject [tex](100 -90.72) =  9.2\%[/tex] of the shipment , so many of the shipment are rejected