I'm not going to explain how to do it, and I definitely don't want to discourage you from asking these questions here. But I *did* want to mention that I copied your first sentence, verbatim, into Bing search, and its chatbot was able to solve it!
https://tinyurl.com/y54z5v52
Could be fun to test this in future with more of your questions. But as the recent chatbots are notoriously hit-and-miss when it comes to basic maths, please do keep on asking here -- I just thought it might be fun to mention.