10 + 1 + 4 = 15
2025.25
0.0392
2/12 = m/18 ie 12 x m = 2 x 18 ...
20416.6667
0.6833
228 is a multiple of 12 so estimation is not necessary but if you must, then 240/12 = 20
10 + 1 + 4 = 15
18
2025.25
651.1667
8.0833
2025.25
2
0.0392
7.6667
To the nearest whole number it would be 12.