Hello! This is not really a homework question, more of a question of what I should do for "homework", but I hope it is acceptable. My question is regarding a method of finding at which point (if at all) two different numbers, when multiplied, reach the same number. For example, how could I find out that the first common whole number that numbers 1.5 and 2 both share is 6 - 1.5 multiplied by 4 and 2 multiplied by 3. It should be obvious from my question and (lack of) terminology that I know almost nothing about mathematics. I am looking to learn more and will start a course soon, but in the meantime it would help a lot if someone could tell me what this type of method is called and what would be the prerequisite knowledge for understanding it. Many thanks!