Question

A sample of 4 different calculators is randomly selected from a group containing 14 that are defective and 34 that have no defects. What is the probability that at least one of the 4 calculators in the sample is defective

Answer 1

The answer is "0.7616".

Explanation:

Using formula:

`\text{P( at least one de-fective) = 1 - P( all calculators work )}`

`= 1-((34)/(48)* (33)/(47)* (32)/(46)* (31)/(45))\\\\= 1-((34)/(1)* (11)/(47)* (1)/(23)* (31)/(45))\\\\=1-((11594)/(48647))\\\\=(48647-11594)/(48647)\\\\=(37051)/(48647)\approx 0.7616`