Сравнить значения выражений: а) 5/33 - (7/11-1/3) и 5/33 + (1/3-7/11)

б) 7/20:3/4+1/5 и 7/20: (3/4+1/5)

А) 5/33 - (7/11-1/3) = 5/33 - 7/11+1/3 и 5/33 + (1/3-7/11) = 5/33+1/3-7/11. те выражения равны б) 7/20:3/4+1/5 = 7*4/20*3 + 1/5 = 7/15+1/5=10/15=2/3

и 7/20: (3/4+1/5) = 7/20 / ((3*5+4) / 20) = 7/20 / 19/20=7/20 * 20/19 = 7/19

2/3=38/57, а 7/19=21/57, т. к 38/57>21/57. то 7/20:3/4+1/5 > 7/20: (3/4+1/5)