The J.O.Supplies Company buys calculators from a non-US supplier.The probability of a defective calculator is 10 percent.If 10 calculators are selected at random,what is the probability that 3 or more of the calculators will be defective?
A) .0702
B) .2639
C) .0016
D) 0

Question

Quizplus · Accepted Answer

The probability of getting 3 or more defective calculators is 1 - the probability of getting 0, 1, or 2 defective calculators. The probability of getting 0 defective calculators is (0.9)^10 = 0.3487. The probability of getting 1 defective calculator is 10 * (0.1) * (0.9)^9 = 0.2439. The probability of getting 2 defective calculators is 45 * (0.1)^2 * (0.9)^8 = 0.1350. Therefore, the probability of getting 3 or more defective calculators is 1 - 0.3487 - 0.2439 - 0.1350 = 0.2724.

The JOSupplies Company Buys Calculators from a Non-US Supplier