limits and probability

probabilty that a number is divisible by a1 is 1/a1
probabilty that a number is divisible by a2 is 1/a2
probabilty that a number is divisible by a3 is 1/a3

they are independent of each other!

I think that the answer should be (1-1/a1)(1-1/a2)(1-1/a3)

the above independence is something most of you will raise fingers on.

but i thin kpart 1 and 2 the answer will be none of these...

part 3 is not visible probperly!