A certain manufactured item is visually inspected by two different inspectors. When a defective item comes through the line, the probability that the first inspector misses it is 0.1. Of those that get past the first inspector, the second inspector will "miss" 5 out of 10. What fraction of defective items get by both inspectors?

Respuesta :

The fraction of a defective item getting by both inspectors is [tex]\frac{5}{100}[/tex] = [tex]\frac{1}{20}[/tex]

Step-by-step explanation:

Step 1; Assume that the probability of the first inspector missing a defective part is P(A) and the probability of the second inspector missing those that do get past the first inspector is P(B).

Step 2; It is given that P(A) = 0.1, we convert this into a fraction so that the final probability will be a fraction and not a decimal.

P(A) = 0.1 = [tex]\frac{1}{10}[/tex].

It is given that the second inspector misses 5 out of 10 that get past the first inspector, so P(B) = [tex]\frac{5}{10}[/tex].

Step 3; To calculate the probability of both inspectors missing a defective part, we multiply both the probabilities.

P(A and B happening) = P(A) Ă— P(B) = [tex]\frac{1}{10}[/tex] Ă— [tex]\frac{5}{10}[/tex] = [tex]\frac{5}{100}[/tex] = [tex]\frac{1}{20}[/tex] = 0.05%. So there is a 0.05% chance of both inspectors missing a defective part.