Easiest would be to just manually come up with a list of equations. Make enough and it should work.
Other ideas could be to randomly gen two numbers and an operator repeatedly. It’s kind of shooting in the dark idea. You’d keep trying combinations till you get a result close enough. You’d probably want to discard any results that aren’t integers too.
To make it work faster you could take the result and change it by a small amount, generate one number and use some algebra to calculate the other.
Another idea is to make a big list of all numbers in a range combined together with each operator. We’d throw out all the non integer results and then sort the whole list by the result. Then to use you’d pick a random one from the list then jump a random amount away to another index for the other equations.
Anyways just some random ideas. No pun intended. Maybe some of it could give you a possible approach to try.