Вычислите рациональным способом :
3/11 ×8/17 +20×4 13/27 +8/11 ×8/17 - 13 /27 ×20

= 8/17 * (3/11 + 8/11) + 20 * (4 13/27 - 13/27) = 80 8/17
1) 3/11 + 8/11 = 11/11 = 1
2) 4 13/27 - 13/27 = 4
3) 8/17 * 1 = 8/17
4) 20 * 4 = 80
5) 8/17 + 80 = 80 8/17