Xiao Ming took 100 and bought a bottle of mineral water for four yuan, which happened to be an activity of four get one free. How many bottles of mineral water did he buy?

4 yuan sells a bottle of mineral water, and then 100 yuan buys it, so you can buy 100÷4=25 bottles of mineral water, and then according to the meaning of the question, buy four bottles to get one bottle, 25438+0 = 6 bottles, which means six bottles, 25+6 = 36438+0. One thing that needs attention in this topic is to buy four and get one free. It should be noted that this buy four get one free includes the mineral water you really paid for, but it does not include the six bottles of water you sent. Don't count too much.