A certain family has 3 sons: Richard is 6 years older than David, and David is 8 years older than Scott. If in 8 years, Richard will be twice as old as Scott, then how old was David 3 years ago?	Choose the correct choice from the following answers
A) 11	B) 10	C) 12	D) 14	E) 16
Let's say   Age of Richard is "R"   Age of David is "D"   Age of Scott is "S"   Now   Richard is 6 years older than David,   i.e. R = D +6   David is 8 years older than Scott   i.e. D = S +8   If in 8 years, Richard will be twice as old as Scott   i.e. R+8 = 2x(S+8)   i.e. R+8 = 2S + 16   i.e. R = 2S+8   But R = D+6 = (S+8)+6 = S+14   therefore, 2S + 8 = S +14   i.e. S = 6   i.e. R = 20   i.e. D = 14   Now,   how old was David 3 years ago?   i.e. D-4 = 14-3= 
<gadget id="calculator">14-3</gadget>
<output>11</output>
11 years   11NSWER:11
<result>A</result>
A certain family has 3 sons: Richard is 6 years older than David, and David is 8 years older than Scott. If in 8 years, Richard will be twice as old as Scott, then how old was David 3 years ago?