But that’s just an assumption, right?
For example, if we say one dollar is one hundred yen, then one can of $1 coca cola is one hundred yen, right?
Since seeing that pile of money on her bed, crazy assumptions have been flying around in my head.
A temporary determination is something you're not totally sure about. You've decided to think of something in a certain way, but only for now. If more information comes to light, you may change. That's why this word means assumption or hypothesis.
This is a jukugo word, which usually means on'yomi readings from the kanji. If you know the readings of your kanji you'll know how to read this as well.