X=3 or 3.5, I know that it isn't a direct answer but you asked this question yesterday and have gotten nothing so I will help narrow it down for you.
Something is strange in the wording of the question. "Of the division problems, 4/9 of the problems he got incorrect. What fraction of the division problems did Gavin get incorrect?" :) Well 4/9 of course. One statement answers another. Maybe they wanted the fraction of those wrong answers were in relation to the entire test???

...............
Answer:
Step-by-step explanation:
2^6 because
2 times 2 times 2 times 2 times 2 times 2 is 64
2 times 2 is 4 times 2 is 8 times 2 is 16 times 2 is 32 times 2 is 64
Answer:
5.76e-8
Step-by-step explanation:
(7.2x10^-4)(8.0x10^-5)
5.76e-8