Ten years ago, the age of Peter was one-third the age of Jacob at that time. The present age of Jacob is 12 years more than the present age of Peter. Find the present age of Peter?	Choose one
A) 15 B) 11 C) 18 D) 16 E) 20
D   16   Let the present ages of Peter and Jacob be 'a' and 'b' respectively.   a - 10 = 1/3 (b - 10) --- (1)   b = a + 12   Substituting b = a + 12 in first equation,   a - 10 = 1/3 (a + 2) =&gt; 3a - 30 = a + 2= 
<gadget id="calculator">+ 2</gadget>
<output>2</output>
&gt; 2a= 32 =&gt; a = 16.
<result>D</result>
Ten years ago, the age of Peter was one-third the age of Jacob at that time. The present age of Jacob is 12 years more than the present age of Peter. Find the present age of Peter?