In these two videos we talk about how to convert numbers in the decimal system to some other base and vice versa. We also discuss how many zeroes will be there at the end of a number in a different base. We also talk about adding, subtracting and multiplying in a different base.

These videos belong to the Number System section of Quantitative Aptitude for the Common Admission Test (CAT). Please note that CAT 2009 is going to be online and a computer based test.