[HELP] Investing Nifty50, is it rational to assume a 15% rate of return?

So yesterday I was thinking about investments. My friend, who's also a techie, was like, "Dude, just put your money in Nifty 50 and chill for 20 years." He said we could expect around 15% returns annually. I was like, "Bro, are you sure?"

I did some quick math using the compound interest formula. If you invest in Nifty 50 now, and leave it for 20 years, it needs to hit 392,796 from its current 24,000 to give us that 15% return. That’s crazy high, right?

Anyway, we debated a bit. He says it's possible, given India's growth story and all. But honestly, getting a 15% return consistently over two decades is ambitious. It’s better to have a balanced expectation, maybe around 10-11%, and be pleasantly surprised if it does better.

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