Question

How do you do this question?

Answer 1

0.488

Explanation:

Use binomial probability:

P = nCr pʳ qⁿ⁻ʳ

where n is the number of trials,

r is the number of successes,

p is the probability of success,

and q is the probability of failure (1−p).

Here, n = 3 and p = 0.2.

The complement of at least 1 is at most 0.

P(r ≥ 1) = 1 − P(r = 0)

P(r ≥ 1) = 1 − ₃C₀ (0.2)⁰ (0.8)³⁻⁰

P(r ≥ 1) = 1 − (0.8)³

P(r ≥ 1) = 0.488