If the average (arithmetic mean) of the four numbers K, 2K + 3, 3K – 5 and 5K + 1 is 85, what is the value of K?
Pick: A) 11 B) 15 3/4 C) 31 D) 23 E) 25 3/10
K + 2K +3 + 3K - 5 + 5K +1 = 11K -1   (11K -1)/4 = 85   11K = 85 * 4 +1 = 340 +1= 
<gadget id="calculator">340 +1</gadget>
<output>341</output>
341   K= 253 / 11 = 31.   Answer 31.
<result>C</result>
If the average (arithmetic mean) of the four numbers K, 2K + 3, 3K – 5 and 5K + 1 is 85, what is the value of K?