Question 611115
Since order matters, you don't want to be using combinations, C(x,y).<br>
At any one time the probability of of a string quartet would be 3/8. Three string quartets over a total of 8 tracks. Similarly the the probability of a vocal is 4/8 or 1/2 and the probability of a piano is 1/8.<br>
The probability of a vocal, then a string quartet and then a piano piece is the product of those probabilities:
{{{(1/2)*(3/8)*(1/8) = 3/128}}}