Time to attain goal: Can you please help resolve this problem? Greatly appreciated?

You are able to deposit $850 in a bank CD today, and you withdraw the money only once the balance is $1000. If the bank pays 5% interest, how long will it take to attain your goal?|||Unanswerable with the info given. There are multiple types of ways this can be calculated. Mainly two. There is compound interest, and some other kind of interest for which I forget the name. Now then, compound interest is the type of interest typically used, it has interest on your interest(unlike the other type), now for compound interest they compound it only certain times. Most banks compound quarterly, some do it biannually...So it does vary. But in essence it will take about 3 years.