Please help with this question, thank you

Question

1. In a manufacturing process it is estimated that 0.1% of the products are defective. If a client places an order for 25 of the products, what is the probability that at least two of them are defective?

Please provide a good, detailed explanation for this question, thank you. How would you take x > 2 into the formula P(x) = _nC_xp^xq^n-x

Answer 1

Apologies. I misread the question last time that I answered. To find P(d>= 2), you calculate 1- P(0) - P(1).

the formula is correct for 0 and 1, just not necessary as

P(0) = .999²⁵ (25 tries no defect) and

P(1) = 25 *(.001)(.999)²⁴

Both of these obey the equation for n=25 and k = 0 and 1