Step-by-step explanation:
In order to compute correctly the sum of the two terms, we have to rewrite one of them such that they have the same exponent.
The two terms are:


For instance, we can re-write the second term such as it also has a power
. In order to do that, we have to move the decimal point one place to the left, therefore:

At this point, the two numbers have the same exponent, so we can just add them together by adding the bases and keeping the same exponent, -2:
