感觉答案是错的,多算了一部分钱感觉像是
做过的求助一下？

Annual prescription drug costs are modeled by a two-paramete r Pareto distribution with
θ =2000  and  α = 2 .

A prescription drug plan pays annual drug costs for an insured member subject to the
following provisions:

(i)   The insured pays 100% of costs up to the ordinary annual deductible of 250.

(ii)  The insured then pays 25% of the costs between 250 and 2250.

(iii)   The insured pays 100% of the costs a bove 2250 until the insured has paid 3600 in
total.

(iv)   The insured then pays 5% of the remaining costs.

Determine the expected annual plan payment.


答案用0.75(E(X^2250)-E(X^250)+0.25(E(X)-E(X^5100))


但是这个式子的第一项从2250之后不是还会按S（2250）概率付出0.75*2000的钱吗，按道理是不是要扣掉，即减去S(2250)*0.75*2000  ？