Arnold and Danny are two twin brothers that are celebrating their birthday. The product of their ages today is smaller by 11 from the product of their ages a year from today. What is their age today?  Pick one
A) 2.  B) 4.  C) 5.  D) 7.  E) 9.
ad = (a+1) (d+1) -11   0= a+d-10   a+d = 10   a=d (as they are twin brothers)   a=d=5   5. is the answer
<result>C</result>
Arnold and Danny are two twin brothers that are celebrating their birthday. The product of their ages today is smaller by 11 from the product of their ages a year from today. What is their age today?