I discovered on Steam a free game which simulates electronic circuits, the Electronics Circuits Simulator, which is part of Circuit Warz.
In this game, you pass through 7 levels, at each level you have to find the right values of components to obtain the desired value in a circuit variable. This video is a gameplay, where I solve all the 7 levels.
All 7 levels’ schematics and equations, except the level 4, where there’s a mistake.