smilexd66

Ответ:

11/20

Пошаговое объяснение:

1) 1/4 + 0.8 = 1/4 + 8/10 = 1/4 + 4/5 = (5 + 4*4)/(4*5) = (5+16)/20 = 21/20 = 1 1/20;

1) 1/4 + 0.8 = 1/4 + 8/10 = 1/4 + 4/5 = (5 + 4*4)/(4*5) = (5+16)/20 = 21/20 = 1 1/20;2) 1/4 + 0.8 = 0.25 + 0.8 = 1.05