81
Объяснение:
30 5/6 - (7 1/3 + 2 1/4) : 0,25 = 81
1) 7 1/3 + 2 1/4 = 25/3 + 9/4 = (100 + 27)/12 = 127/12 = 10 7/12
2) 30 5/6 - 10 7/12 = 185/6 - 127/12 = (370 - 127)/12 = 243/12 = 20 1/4
3) 20 1/4 : 25/100 = 20 1/4 × 100/25 = 81/4 × 4/1 = 81
81
Объяснение:
30 5/6 - (7 1/3 + 2 1/4) : 0,25 = 81
1) 7 1/3 + 2 1/4 = 25/3 + 9/4 = (100 + 27)/12 = 127/12 = 10 7/12
2) 30 5/6 - 10 7/12 = 185/6 - 127/12 = (370 - 127)/12 = 243/12 = 20 1/4
3) 20 1/4 : 25/100 = 20 1/4 × 100/25 = 81/4 × 4/1 = 81