The average age 15 members of a committee are the same as it was 2 years ago, because an old number has been replaced by a younger number. Find how much younger is the new member than the old number?
Select.
A) 18 B) 99 C) 30 D) 26 E) 12
15 * 2= 
<gadget id="calculator">15 * 2</gadget>
<output>30</output>
30 years   Answer: 30
<result>C</result>
The average age 15 members of a committee are the same as it was 2 years ago, because an old number has been replaced by a younger number. Find how much younger is the new member than the old number?