If a is an integer larger than 1, and x=60a, then x must be a multiple of which of the following? Pick: A) 8 B) 9 C) 12 D) 18 E) 120
X must be divisible by 60 .   a , an integer less than 1 means a could be 0,-1,-2,....... and x = 60a   so if a= 0, x = 0*60= 
<gadget id="calculator">0*60</gadget>
<output>0</output>
0 is divisible by 12 ( recall 0 is divisible by any integer)   if a= -1, then -60 is divisible by 12 but not 8,9,18 and 120 , if a-2 , then -120 is divisible by 60 and so on   Answer is 12
<result>C</result>
If a is an integer larger than 1, and x=60a, then x must be a multiple of which of the following?