Yep, this is a marketing problem. Your users' goal is to learn, but they also want to expend as little effort as possible. They'll love it if you just tell them the answers, but you're also doing them a disservice by doing so.

Same problem exists for all educational apps. Duolingo users have the goal of learning a language, but also they only want to use Duolingo for a few minutes a day, but also they want to feel like they're making progress. Duolingo's goal is to keep you using Duolingo, and if possible it'd be good for you to learn the language, but their #1 goal is to keep you coming back. Oddly, Duolingo might not even be wrong to focus primariliy on keeping you moving forward, given how many people give up when learning a new language.