Question

Every evening, Yuval finishes work at a random time and arrives at a bus stop. At this station, two buses stop: number `7`, which goes to Yuval's house, and number `13`, which goes to the house of his friend Shlomi. Yuval gets on the first bus that arrives and, depending on that, goes to Shlomi's or home.

After a while, Yuval notices that after work, he goes to Shlomi's about twice as often as he goes home. He deduced from this that bus number `13` arrives twice as frequently as bus number `7`.

Is Yuval necessarily correct?