7в. 14 - 13.2 : (3 11/24 - 2 4/15)
14 - 13.2 : (74/21 - 34/15)
14 - 13.2 : 44/35
14 - 10.5 = 3.5
7г. 20 - 18.6 : (6 11/15 - 4 3/20)
20 - 18.6 : (101/15 - 83/20)
20 - 18.6 : 31/12
20 - 7.2 = 12.8
13а. 0.3(4x + 5) - 4(3 + 0.3x) - 5.2(-8x - 6)
1.2x + 1.5 - 12 - 1.2x + 41.6x + 31.2
20,7 + 41.6x
13в. x - 1 1/3 + 2.8 - x - 1.3
1/6