A calculator manufacturer checks for defective products by testing 3 calculators out of every lot of 12. If a defective calculator is found the lot is rejected.

a) Suppose 2 calculators in a lot are defective. Outline two ways of calculating the probability that the lot will be rejected. Calculate this probability

(Do I use the probability distribution here? This question is a hypergeometric distribution

b) The quantity control department wants to have at least 30% chance of reject lots that contains only one defective calculator. Is testing 3 calculators in a lot of 12 sufficient? If not how would you suggest they alter their quality control techniques to achieve this standard? Support your answer with mathematical calculations

Any help would be nice