What is the meaning of "to the tune of something"?

Native speaker’s answer
Rebecca
"To the tune of [number]" is an informal expression often used when speaking about large amounts of money. It means "amounting to" or "involving." Thus, "to the tune of 400 million dollars" means "amounting to 400 million dollars." Ex: The man offered his ex-wife a divorce settlement to the tune of $10 million dollars. Ex: The businessman was caught through a tax fraud investigation. He was in debt to the Tax Bureau to the tune of $2.3 million dollars.