[Edited out]
Therefore, he should invest five, ten, or 15% of that $100 in Bitcoin and keep the rest invested in local currency or gold as an emergency fund so that he can use it when needed.
Investing like 5-15% of the $100 in Bitcoin and the remaining percentage ( probably 75-95% in gold or local currency)may sound smart but it may not really be the best idea especially for people in countries with high inflation rate, where the value of their local currency keeps dropping on a daily basis. And the implication of this is that the money you have today might buy you lesser and lesser things as day keeps rolling by.
Gold may seem stable but it doesn't grow as fast as Bitcoin does overtime.
If you understand Bitcoin well you will notice that it is better to push up your Bitcoin allocation to maybe 30-40% due to its high appreciation rate.
Here we are talking about emergency funds. Danger never comes with a message. When a danger comes, you may need money. Now if you invest all your money in Bitcoin, you will find that you are not able to arrange money when you need it.
That is why I said that it is always safe to keep emergency funds in fiat currency even though inflation occurs there.
People earn money and in this case, a certain amount has to be deposited as an emergency fund to use it when they need it. So no matter how much inflation occurs in the currencies of your emergency fund, since you need to save your life, it is better to let inflation occur to save your life.
Understanding this, if someone wants to invest their emergency fund with risk, then I said that they should invest some part of it instead of investing the whole amount.
However, I think it is better to keep the emergency fund in fiat.