How many kids want to play sport's but can't afford it?

From one perspective you could say plenty. Kids may want to get out, play sports, and compete...but can't because their family is dirt poor. Many sports involve a lot of expense. From another perspective, kids can go out and run races against each and do all sorts of other sports with other kids at absolutely no cost whatsoever. So it depends on what sports they may want to do. They can run a race with other kids for free, but could not do motorbike racing against each other for free. Even richer kids may have some sports that are beyond what they can afford. So there is no definitive answer.