German and french are both very important languages but very time consuming to study. I am from Germany and I know how many people are suffering with the grammer of "der, die, das".
So, anyways, I would definitely take either German or French. Maybe you can take a peek at both languages and see which one you like better.
Source(s): own experience
In international business, the "second" language to English is often French, so that can be quite useful. It's also a handy language to have in American/British/Canadian culture, since a lot of our high culture was, and sometimes still is, influenced by French.
Beyond that, if there's any particular field of business that interests you - say, you'd love to work for Sony, or SAP - then you could study the languages that would be most useful there (Japanese and German, in turn.) Likewise, if you hope to work for the state department/foreign service/CIA, Mandarin or Korean or Arabic are in very high demand.
Otherwise, let your personal interests guide you. In general, people have more fun, and learn a language better, if they have some sort of personal tie to it. Perhaps you are of Italian decent, or you've always wanted to study abroad in Poland, or are really into anime, or the state you want to work in has a lot of Mandarin speakers, or you're hoping to work for a fashion house - let your personal circumstances and interests guide you in your choice.
If you like math, then you might enjoy the German language. It is a very precise and methodical language to learn. I took German, Italian and French in college and I definitely love the German language the most!!!
Majoring in business (and maybe math), French would be good. Fortune 500 companies do a lot of work in French speaking areas. And if you decide, for your graduate degree, to go with the math side of your interests and do something in applied math, then it's very important to speak French.