Answer:
65.3%.
Step-by-step explanation:
The general formula is:
nCr p^r (1 - p)^(n-r) where n = number of trials, p =probability of success on one trial , r = the given number of successes
So for 2, 3 or 4 success ;
probability = 5C2 (0.4)^2 (0.60)^(5-2) + 5C3 (0.4)^3 (0.60)^(5-3)
+ 5C4 (0.4)^4 (0.60)^(5-4)
= 0.3456 + 0.2304 + 0.0768
= 0.6528.
