Hello! I'm looking to write a halflife problem like this. Fermium-257 has a halflife of 100 years. If you have [x] grams of it now, how much will you have in [y] years? However, I want y to be only in multiples of 100, and as far as I can tell, I'm only allowed to define y with integers at best. So, what I'm trying to figure out, is it possible to write in the question with a formula? Like, instead of [y] years, could I have [y]*100 years? So far it doesn't seem to be working, but I can't think of any other way to do this type of problem. Thanks!

What if you just added the word "hundred" between the [y] and years? So then it could be an integer and it would say "how much will you have in 5 hundred years?". Looks kind of awkward but it gets the point across. Then you can factor the [y]*100 into the equation on the teacher end.