Calculate the Poisson probability for finding unusable glove

Calculate the Poisson probability for finding unusable gloves in a box of 100 if the average is two per box:

A) Using the =POISSON () Function

B) Using the Poisson formula ( see screen shot)

Solution

a)

Note that P(at least 1) = 1 - P(none)

Thus,

P(at least 1 unusable)

=1 - POISSON(0, 2, FALSE)

= 0.864664717 [ANSWER]

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b)

Using the formula,

P(at least 1) = 1 - P(0)

= 1 - (2^0)(e^-2) / 0!

= 1 - e^-2

= 0.864664717 [ANSWER]