When you add numbers what do you do to the exponent?

Answer 1

You can only add numbers if they have the same exponent. If not, you need to scale them so that they do.

Add the mantissae of the numbers (these are the bits before the exponents). That is followed by the common exponent.

For example:

3.1*102 + 3.6*103 = 0.31*103 + 3.6*103 (now the exponents are the same)

= (0.31 + 3.6) *103 or 3.91*103

In this particular example, it is easy enough to check the answer:

3.1*100 + 3.6*1000 = 310 + 3600 = 3910 = 3.91*1000 = 3.91*103