Question

А=5/7 +7/4+9/13, 1/7+1/4+1/13 =?

Answer 1

Ответ: А=5/7 +7/4+9/13=9/13+(5*4+7*7)/28=9/13+69/28=(9*28+69*13)/364=1149/364=3 57/364,

1/7+1/4+1/13 =(7+4)/28+1/13=11/28+1/13=(11*13+1*28)/364= 171/364.

Объяснение: