Răspuns :
[tex] \frac{28}{13} \times 7 = \frac{28 \times 7}{13} = \frac{196}{13} [/tex]
196/13 e numarul de 7 ori mai mare decat 28/13
[tex]7 \times \frac{28}{13} = \frac{7}{1} \times \frac{28}{13} = \frac{7 \times 28}{1 \times 13} = \frac{196}{13} [/tex]