A spinner is separated into 4 equal pieces, as shown below:

Jonathan spins the spinner 10 times. What is the theoretical probability that it stops on the black sector on the last spin?

Getting black is 1/4 of the percentage, and spinning it 10 times gives us 10/40, because there are 40 possible colors to land on when u spin it 10 times. The last spin, is just like any other time you spin it. just because it's the last spin, doesn't make the black sector greater. So the answer is 1/4 or 25%.