In order to give back to customers and promote sales, a tea shop is going to throw dice (throw a unified cube with numbers of 1 to 6 on each side and look up at the points) to win points.

(1) The total number of basic events is 63=2 16 (pieces).

Event A has 4A? 33=24 basic events, ∴ p (a) = 24216 =19;

Event B*** has six basic events, ∴ p (b) = 6216 =136;

Event c: two serial numbers * * *: 1-2, 2-3, 3-4, 4-5, 5-6, totally five cases.

There are two similar possibilities in every situation.

∴ * * There are 5×2×A 13=30 basic events,

∴P(C)=302 16=536，

∴ Event B: The probability of "three identical points" corresponding to the first prize is 136.

Event A: The "three consecutive numbers" correspond to the second prize, and the probability is 19.

Event C: "There are exactly two consecutive numbers and exactly two similarities" and the third prize with a corresponding probability of 536.

The rest of the events correspond to the thank-you prize, and the probability is:

1- 136? 19? 536= 13 18.

(2) Let the obtained integer be a random variable η, and the distribution table can be known from (1) as follows:

? η? 100? 20? 105? ? p？ 136? 19? 536? 3 18eη= 100× 136+20× 19+ 10×536+5× 13 18 = 10。

∴ The overall preferential margin is 10 100= 10%, which can achieve the purpose of controlling costs.