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Probability/Stats Question?

Can someone please help me solve: A survey found that 30% of teenage consumers received their spending money from part-time jobs. If five teenagers are selected at random, find the probability that at least three will have part-time jobs. Please show work. Thank you so much!

Public Comments

1. The number of teenage consumers who received their spending money from part-time jobs out of the five will have a binomial distribution with number of trials n = 5 and probability of success p = 0.3. P(at least three have part time jobs) = P(3 have part time jobs) + P(4 have part time jobs) + P(5 have part time jobs) = 5!/(3!2!) * 0.3^3 * 0.7^2 + 5!/(4!1!) * 0.3^4 * 0.7^1 + 5!/(5!0!) * 0.3^5 * 0.7^0 = 0.1323 + 0.02835 + 0.00243 = 0.16308