K + 2K +3 + 3K - 5 + 5K +1 = 11K -1
(11K -1)/4 = 41
11K = 41 * 4 +1 = 164 +1 = 165
K = 165 / 11 = 15.
If the average (arithmetic mean) of the four numbers K, 2K + 3, 3K – 5 and 5K + 1 is 41, what is the value of K?
[a]  41
[b]  15 3/4
[c]  22
[d]  23
[e]  25 3/10