sundetamanjol  7 / 25 + 1/3 / 5/24 - 22/25 / ( 4.5 + 2/5 ) / 7/20 = 
1) 4 1/2 + 2/5 = 4 5/10 + 4/10 = 4 9/10 = 2209/3500
2) 22/25 / 4 9/10 = 22/25 / 49/10 = 22/25 * 10/49 = 220/1225 = 44/245
3) 1/3 / 5/24 = 8/5 = 1 3/5
4) 7 / 25 = 0.28
5) 0.28 + 1 3/5 = 7/25 + 1 3/5 = 7/25 + 1 15/25 = 1 22/25
6) 1 22/25 - 44/245 = 1 5390/6125 - 1100/6125 = 1 4290/6125
7) 1 4920/6125 / 7/20 = 11045/6125 / 7/20 = 2209/3500 не знаю сокращается или нет