Respuesta :

3/7 and 1/2    14 is the common denominator    at the end it is   6/14  and 7/14
3/7 and 1 1/2

Now look at the two denominators: 7 and 2.

Because 7 and 2 are relatively prime, their least common multiple is:
7*2= 14

Therefore, 14 is a common denominator for 3/7 and 1 1/2.

Hope this helps~