Okay, let’s talk about this problem: 15 is 30 of what number? It seems quite simple, but I still want to share my experience with you guys.

So, I found some online tools that might help me do the calculation. They are called Symbolab, Mathway, Quickmath, or something. There are also some other tools that can simplify equations. I think I can use these tools to verify my answer, but I want to try to figure it out myself first.
I know that to solve this kind of problem, I need to convert the percentage to a decimal or fraction first. So, 30% should be written as 0.3 or 3/10. Let’s use 0.3 for now. The problem is asking: 15 is 0.3 of what number? I can write this as an equation:
- 15 = 0.3 x
Here, ‘x’ is the number I’m trying to find. To get ‘x’, I need to get it alone on one side of the equation. I can do that by dividing both sides of the equation by 0.3:
- 15 / 0.3 = (0.3 x) / 0.3
This simplifies to:
- 50 = x
So, it seems like the answer is 50. 15 is 30% of 50. I guess I could just stop here, but I am curious to see if those online calculators give me the same result. I picked Symbolab and typed in the equation “15 = 0.3 x”.

Guess what? Symbolab showed me the same solution, 50. It also graphed the equation, which looks pretty cool. It seems like my calculation was correct.
I also tried Quickmath, I simply entered the equation. Quickmath solved it and gave me the same answer, 50. That’s great.
So, my own calculation and the online tools all agree that 15 is 30% of 50. That was a fun little exercise! I hope you found this walkthrough helpful, even if it was for a pretty simple problem. Next time, maybe we’ll try a more complex one. Feel free to ask me any questions if you have them!