Probability question

Question

what is the probability of getting 8 or more tails from 10 flips of an unfair coin that is biased to land on heads 60% of the time?

Answer 1

8 tails = 2 heads. Probability = C (10,2) p²q ⁸

9 tails. C (10,1) p¹ q ⁹

10 tails : q ¹⁰

^{p = 0.6, q = 1-p = 0.4}

Calculate these and add them up.

On a TI-84 you can do it directly. 8 or more tails is 2 or less heads

binomcdf

trials = 10

p = 0.60

x value = 2

0.0123