Respuesta :

13 is the greatest common divisor of 39 and 91.

[tex]13 \times 3 = 39 \\ \\ 13 \times 7 = 91[/tex]

Answer:

  13

Step-by-step explanation:

39 = 3·13

91 = 7·13

The only common factor is 13.

  GCD(39, 91) = 13