1) 4 - 2.6 = 1.4
2) 4.3 × 1.4 = 6.02
3) 1.08 ÷ 1.2 = 0.9
4) 6.02 + 0.9 = 6.92
В 5метрах 500 см.В 4дм 40 см 82м 8.200 см
(6/7 - y) + 2/7 = 5/7
6/7 - y = 5/7 - 2/7
6/7 - y = 3/7
y = 6/7 - 3/7
y = 3/7
(6/7 - 3/7) + 2/7 = 5/7
5/7 = 5/7
{20 - (3а - 7)} /10 = 9/10
20 - (3а - 7) = 9/1 = 9
20 - (3а - 7) = 9
3а - 7 = 20 - 9
3а - 7 = 11
3а = 7 + 11
3а = 18
а = 18 : 3
а = 6