The sequence seems to be that you add 1 and then multiply by 2, and then add 1 and multiply by 3, so I would assume you do 9 + 1 = 10, and then multiply by 4 to get 40 as your next number. I hope this helps!
0.19880716 should be your answer
Sorry if wrong
12 1/4 - 3 3/5 =
49/4 - 18/5 =
245/20 - 72/20 =
173/20 =
8 13/20
