A certain elevator has a safe weight limit of 2,500 pounds. What is the greatest possible number of people who can safely ride on the elevator at one time with the average (arithmetic mean) weight of half the riders being 150 pounds and the average weight of the others being 160 pounds?
Choose the correct choice from the following answers:
A) 7	B) 8	C) 9	D) 10	E) 16
Lets assume there are 2X people.   Half of them have average weight of 150 and other half has 160.   Maximum Weight is = 2500   So 150*X + 160*X = 2500   =&gt; 310X = 2500   =&gt; X is approximately equal to 8.   So total people is  2*8= 
<gadget id="calculator"> 2*8</gadget>
<output>16</output>
16   Answer 16.
<result>E</result>
A certain elevator has a safe weight limit of 2,500 pounds. What is the greatest possible number of people who can safely ride on the elevator at one time with the average (arithmetic mean) weight of half the riders being 150 pounds and the average weight of the others being 160 pounds?