I would say the best estimate would be 9 because the real answer is 8.71 and if you round that to the 1 place the answer would be 9.
20 - 7 = 13
8 - 13 = 5
13 + 5 = 18
20 - 18 = 2
So two is your answer because.....
13 + 5 + 2 = 20
48 steps........ i just know lol