Melody

This is how I tackled this problem.

I said let there be 1000 people present.  It is easier to work with real numbers.

90 % are economists, which is 900 economists.

15% of those are shy, so that is  135 shy economists

10% of the 1000 people are statisticians so that is 100 statisticians.

80% of those are shy so that is 80 shy statisticians.

So there are 135+80=215 shy people at the gathering. And 80 of them are statisticians.

So that gives a probability of  80/215 = 16/43

Why don't you give yourself some points?

Good work AnimalMaster, that is absolutely correct  

I do not understand what you are trying to ask.

Thanks CalculatorUser!      

Very nicely executed!

What does that even mean?

The other question was different.

I answered the other one recently but obviously not on the thread that you just found.