Question

4d^-3 multiplyed by d^18

Answer 1

4*d^(-3)*d^18 = 4*d^(18-3) = 4*d^(15).  The trick here is to combine the exponents.

Another way to write this problem would be:

4*d^18
---------- .  Here d^18 divided by d^3 results in d^15, so again the final 
  d^3         answer is 4*d^15.