Найдите значение выражения 5/4-2.1-1/5 0.86:43/20 9 * (7/36+5/12-1/6) 1,23*45,7/12.3*0.457

1) 5/4 - 2,1 - 1/5 = 5/4 - 21/10 - 1/5 = (5 * 10 - 21 * 4 - 1 * 8) / 40 = (50 - 84 - 8) / 40 = - 42/40 = - 21/20 = - 1 1/20;

2) 0,86 : 43/20 = 0,86 * 20/43 = 17,2/43 = 172/430 = 86/215 = 0,4;

3) 9 * (7/36 + 5/12 - 1/6) = 9 * (7 * 1 + 5 * 3 - 1 * 6) / 36 = 9 * (7 + 15 - 6) / 36 = 9 * 16/36 = 9 * 8/18 = 9 * 4/9 = 4;

4) 1,23 * 45,7/12,3 * 0,457 = 56,211/5,6211 = 562110/56211 = 10.