Alphabet permutations

The classical latin alphabet {a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r,s,t,u,v,w,x,y,z} contains 20 consonants and 6 vowels.

What is the probability that in a permutation of this alphabet, there are no consecutive vowels?

Answer format: P/Q with P and Q coprime.

[My timing: < 1 sec]