I have done part A but think i am way off. Not even sure what distrubition rules i can follow.

Edit from my notes I have found this to be a cumulutive prob function.

Part a

K= 1 I get 1-.75 = .25

K=2 1-.25 = .75

K=3 i get 1- 11/12 = 1/12

Part b

P(x < 3/2) U P( X > 1/2)

= F(3/2)F(1/2)

Working this out i get 1/2

Could someone confirm if this is correct please

Thanks in advance!