Question 150905
Art=a
Ben=b
Cal=c


a=b
a=c+1


c+1+c+1+c=59
3c+2=59
3c=57
c=19


Cal is a teen now.  Subtract 7.
19-7=12


Cal was 12
Art was 13
Ben was 13


Art and Ben were teenagers 7 years ago.