Have you ever heard the expression, “go for the low-hanging fruit”? It means do the easiest task first, as the nearest “fruit” is the easiest to get. Then you can focus on more complicated tasks or goals. Studying can be like that. You can succeed the most in subjects which you like or are good at. Sometimes we focus too much attention and effort on subjects which we perform poorly. A great tennis player doesn't spend time trying to improve his golf game, he focuses on his tennis skills. Maybe you should also, “focus on your strengths”!