Shenzhen weather data

(1) Let the probability of lightning weather on a certain day in August be p, which is known as p = 14.57 35438+0 = 0.47.

Therefore, the probability of lightning weather in just two days is p = c 32× 0.472× (1-0.47) = 0.351231≈ 0.35.

(2) from the known x ~ b (12,0.47).

So the mathematical expectation of x is e (x) = 12× 0.47 = 5.64.

The variance of x d (x) =12× 0.47× (1-0.47) = 2.9892.

So the mathematical expectation and variance distribution of X are 5.64 and 2.9892.