You have a whole pizza in the refrigerator. On your first trip to the refrigerator, you eat half the pizza. On each successive trip, you eat half of the remaining pizza. After five trips to the refrigerator, what fractional part of the pizza have you eaten?
Well, you will eventually finish the pizza....after infinite years. It's probably moldy by then, so not a good way to eat pizza. I wonder what this guy is doing with his/her life to eat HALF A PIZZA in one sitting, add later eating on fourth. Just eat the whole pizza directly! Then there would not have to be any math problem, OR moldy pizza.
All things aside, it is a word problem, and most of the time, they are pretty unrealistic.
For the problem:
Sure, we COULD just keep on figuring out each half of the pizza, and yadda yadda yadda, but there is an easier way. But before we get into the easier way, let's go through the hard way, just to justify the easy way.
Description: This is the way for people with a lot of time, just like the guy who keeps on eating half his pizza instead of the whole.
Start: 1 whole
Half 1: 1/2
Half 2: 1/4
Half 3: 1/8
Half 4: 1/16
Half 5: 1/32
Conclusion: That dude must have a lot of time up his sleeve to be forever eating pizza and solving math problems the hard way.
Desription: For people who like exponents. If you are allergic to them, then do it the hard way. We won't judge. (Unless you are that dude who keeps on eating half his pizza)
Simply put, this question is just asking for 2^-5, which is basically halfing as you go. This is:
1/2^5 = 1/32
Conclusion: We now know that whoever tried this method is immune to exponents, yet still like to eat moldy pizza.