Answer:
0.0091 = 0.91% probability that the ant ends up at point (2,5)
Explanation:
What is needed to move from the point (0,0) to the point (2,5) after 10 moves:
5 moves of up by 1 unit.
2 moves of right by 1 unit.
10 - (5 + 2) = 3 standing still.
Probability:
2 moves of right by 1 unit, each with 0.3 probability.
5 moves of up by 1 unit, each with 0.2 probability.
3 standing still, each with 0.5 probability.
Number of ways this can happen:
Arrangments of 10 moves, with 2, 5 and 3 repetitions. So

Probability:

0.0091 = 0.91% probability that the ant ends up at point (2,5)