you can make 4 combinations
1. 12 2. 213. 224. 235. 246. 257. 268. 279. 2810. 2911. 3212. 4213. 5214. 6215. 7216. 8217. 92So 17
Example: First you start by using (in this case) the four. You multiply it first by the two, then by the one. (I apologize for the asterisks, they were necessary to keep the spacing.) 12 *12...
Yes - from 11/11 = 1 to 99/11 = 9, this is the case.
99