A father said to his son, "I was as old as you are at present at the time of your birth." If the father's age is 60 years now, the son's age 10 years back was?
Select.
A) 12yr B) 15yr C) 14yr D) 10yr E) 20yr
Let the son's present age be x years   Then, 60-x = x   x = 30   Son's age 10 years back = 30-10= 
<gadget id="calculator">30-10</gadget>
<output>20</output>
20years   Answer is 20yr
<result>E</result>
A father said to his son, "I was as old as you are at present at the time of your birth." If the father's age is 60 years now, the son's age 10 years back was?