The average age of a family of four members is 25 years. If the age of the youngest member be 15 years then what was the average age of the family at the time of the birth of the youngest member?
Choose the correct choice from the following answers:	A) 13.5	B) 14	C) 15	D) 13.33	E) 16
Explanation :   At present the total age of the family = 4 * 25= 
<gadget id="calculator">4 * 25</gadget>
<output>100</output>
100   The total age of the family at the time of the birth of the youngest member= [100-15-(15*3)= 
<gadget id="calculator">100-15-(15*3)</gadget>
<output>40</output>
40   Therefore, average age of the family at the time of birth of the youngest member= 40/3   = 13.33   Answer : 13.33
<result>D</result>
The average age of a family of four members is 25 years. If the age of the youngest member be 15 years then what was the average age of the family at the time of the birth of the youngest member?