A frog begins at negative twenty-one on a number line. The frog hops positive sixteen times and then hops negative four times. At what value does the frog end?

negative forty-one

negative nine

positive nine

negative one

Question

A frog begins at negative twenty-one  on a number line. The frog hops positive sixteen  times and then hops negative four  times. At what value does the frog end? 

 negative forty-one 

 negative nine 

 positive nine 

 negative one

nurali · Answer

-25 + 16 = -9

anonymous · Answer

I have arrived at the same conclusion as Nurali, but through a different way.
-21 + 16 = -5 -4 =-9.