What were the specific amounts of money mentioned in the story of the two Goa gentlemen, and who questioned Sai about it?

In the story of the two gentlemen from Goa, as narrated in Chapter 36, specific monetary amounts are central to the event. Sai Baba asked for a Dakshina of 'fifteen rupees' from one of the men, which was given with joy. The second man, without being asked, offered 'thirty-five rupees' on his own accord, which Sai immediately rejected. The person who questioned Sai Baba about this apparent partiality was Madhavrao, who is also referred to as Shama in the text. He was present at the time and was moved to ask Baba about the differing treatment of the two visitors.