1.A2
1) 12/25 - 7/30 = 72/150 - 35/150 = 37/150
2) 1,8*2,5 = 4,5
3) 0,25 + 0,5 = 0,75
4) 37*0,75/(150*0,074) = (37*750)/(150*74) = 5/2 = 2,5
5) 2,5 + 4,5 = 7
Ответ: 2) 7.
2.A4
1) 11/4 : 11/10 = 11/4 * 10/11 = 10/4 = 5/2 = 2 1/2
2) 2 1/2 + 3 1/3 = 5 5/6
3) 2/5 * 10/3 =4/3
4) 5/2 - 4/3 = 7/6
5) 35/6 : 7/6 = 35/6 * 6/7 = 5
6) 5 : 5/7 = 5 * 7/5 = 7
7 : 0,2 = 70 : 2 = 35
Ответ: 4) 35
3.A2
1) 7/4 : 9/8 = 7/4 * 8/9 = 14/9
2) 7/4 : 2/3 = 7/4 * 3/2 = 21/8
3) 14/9 - 21/8 = 112/72 - 189/72 = -77/72
4) -77/72 * 12/7 = -11/6
5) 20/9 *3/8 = 15/18
6) -11/6 + 15/18 = -33/18 + 15/18 = -18/18 = -1
Ответ: 3) -1