Frank is 14 years younger then John. In 5 years John will be twice as old as Frank. How old will Frank be in four years?  Pick one.
A) 8	B) 10	C) 13	D) 14	E) 16
Frank is 15 years younger then John --&gt; F+14=J;   In 5 years John will be twice as old as Frank (in 5 year John will be J+5 years old and Frank will be F+5 years old) --&gt; J+5=2*(F+5) --&gt; (F+14)+5=2*(F+5) --&gt; F=9;   In 4 years Frank will be 9+4= 
<gadget id="calculator">9+4</gadget>
<output>13</output>
13 years old.   Answer: 13.
<result>C</result>
Frank is 14 years younger then John. In 5 years John will be twice as old as Frank. How old will Frank be in four years?