Good job on the earlier parts!

In fact, you want to use the same method for the last part. After jumping over pad 6, the frog is at pad 7 and must get to pad 10. Remember, however, that since there is a pad 11, the frog can still jump over the food on pad 10, which we need to avoid.

Hence, the possible jumps are 1-1-1, 1-2, or 2-1, with probability 1/8+1/4+1/4 = 5/8 for the last part. Then we just need to multiply all the parts together for the final answer.

Note: The method above works great, as the different cases are not too bad. I also, however, would recommend trying a recursive approach to the problem. If $P_N$ is the probability the frog gets to pad $N$, we know $P_0 = 1$ and $P_3=P_6=0$. How can you write $P_N$ in terms of the previous pads?