Найдите значение выражения : 1)3/5*4/9+1 1/3; 2)1 1/4*2/5-1/3

В) 3/5 : (9/10 – 3/5 ·8/9) = 1 цел 7/11

1) 3/5 · 8/9 = 1/5 ·8/3 = 8/15       2) 9/10 – 8/15 = (3·9–2·8)/30 = (27–16)/30 = 11/30
3) 3/5 : 11/30 = 3/5 · 30/11 = 90/55 = 18/11 = 1 цел 7/11

а)  4 · 1/5 + 4 · 3/7 – 4 · 1/35 = 4·(1/5 +3/7–1/35) = 4·(7+15–1)/35 =

= 4·21/35 = 4·3/5 =12/5 = 2,4


в)  3/2 · 5/6 + 3/2 : 9/10 – 3/2 · 13/18 = 3/2 · 5/6 + 3/2 · 10/9 – 3/2 · 13/18 = 

= 3/2·(5/6 + 10/9 – 13/18) = 3/2 · (15/18 +  20/18 – 13/18) = 3/2 · 22/18 =

= 11/6 = 1 цел 5/6

<span>9(2у -1) – 2(5 + 3у)
18y - 9 - 10 - 6y
18y - 6y - 9 - 10
12y + 1</span>

<span>5a+2(7-a)=5а+14-2а=3а+14
5a-2(7-a) =5а-14+2а=7а-14</span>