What will happen if i buy in two installment and sell them?

Suppose I buy 20 stock at rs 100 and after that the price go down to rs 95 and again i buy 5 stock at rs 95.total buy stock=15. now the stock price is 98.now if i sell 5 stock then which stock will be sold?means the stocks which i bought at rs 100 or the stocks that i bought at rs 95?

Orders will work under first in first out method, so the first order will get cleared