the question asks:

How many 5-card poker hands consisting of 2aces and 3 kings are possible with an ordinary 52-card deck?

this is what i did:

"c"=stands for combination

(4C2) * (4C3) = 6*4 = 24

(52C5) = 259860

so then i divided :

(24)/(259860)= 9.2344630159756210176378243605134e-6

Looks right.
Cept the question asks for the number of possible hands; I would have stopped at 24. But, good job, you went further and gave the probability of drawing such a hand.