Arnold and Danny are two twin brothers that are celebrating their birthday. The product of their ages today is smaller by 13 from the product of their ages a year from today. What is their age today?	Choose one:
A) 2. B) 6. C) 5. D) 7. E) 9.
ad = (a+1) (d+1) -13   0= a+d-12   a+d = 12   a=d (as they are twin brothers)   a=d=6   6. is the answer
<result>B</result>
Arnold and Danny are two twin brothers that are celebrating their birthday. The product of their ages today is smaller by 13 from the product of their ages a year from today. What is their age today?