336
Subtraction means distance on the number line. From 475 to 500 is 25, from 500 to 800 is 300, and from 800 to 811 is 11. Therefore, 811 - 475 = 25 + 300 + 11 = 336. --- A slightly different way to think about it: we know that 475 = 500 - 25, so subtracting 475 is equivalent to subtracting 500 and then adding 25. Well, 811 - 500 = 311, and 311 + 25 = 336.