Given that a is the average (arithmetic mean) of the first nine positive multiples of six and b is the median of the first seven positive multiples of six, what is the ratio of a to b?	Pick.
A) 5:4 B) 10:13 C) 5:6 D) 13:10 E) 4:3
The first nine positive multiples of six are {6, 12, 18, 24,30, 36, 42, 48, 54}   The first twelve positive multiples of six are {6, 12, 18, 24, 30,36,42 }   Both sets are evenly spaced, thus their median=mean:   a=30 and b=24 --&gt; a/b=30/24=5/4.   5:4nswer: 5:4.
<result>A</result>
Given that a is the average (arithmetic mean) of the first nine positive multiples of six and b is the median of the first seven positive multiples of six, what is the ratio of a to b?