Just with Hindi and Chinese you can speak to about 40% of the world's population.
Population-wise yes, but country-wise, it's pretty weak.
With french, english and spanish, you cover North-America, Central and South-America but Brazil, Australia and probably many of the countries around, well over 50% of Africa, and some european countries (France, Spain, Belgium, Switzerland...).
You don't cover Asia and Eastern Europe isn't really covered either as they are not known to really speak english.
But it's still quite a good cover.
Anyway, french is my language, I can speak and understand english quite well, but spanish is a weak link. I would have a small use to it but it would be nice. Right now, I just have a few small memories from school.