The ratio of a to b to c is 2 to 3 to 4, and a, b, c are positive integers. If the average (arithmetic mean) of the three numbers is 51, what is the value of a? Pick one: A) 24 B) 25 C) 28 D) 32 E) 34
Let a=2k, b=3k, and c=4k.   a+b+c = 2k+3k+4k = 9k   Since the average is 51:   9k/3 2 +3 +4= 
<gadget id="calculator">2 +3 +4</gadget>
<output>9</output>
9k   Since the average is 51:   9k/3= 51   3k = 51   k=17   Then a=34.   The answer is 34.
<result>E</result>
The ratio of a to b to c is 2 to 3 to 4, and a, b, c are positive integers. If the average (arithmetic mean) of the three numbers is 51, what is the value of a?