1)) -5,3:а- 3,18=-3,78;
-5,3:а= -3,78+ 3,18;
-5,3:а= -0,68;
-5,3 : -0,6= а;
а= 53/10 : 6/10;
а= 53/10• 10/6;
а= 53/6= 8 5/6.
Проверка
-5,3: 8 5/6 - 3,18= - 53/10: 53/6- 3,18= -53/10• 6/53- 3,18= -1/10• 6/1- 3,18= -6/10- 3,18= -0,6- 3,18= -3,78.
2))) -2/3 :b -1 5/9 = 1 2/3;
-2/3: b - (9•1+5)/9= (1•3+2)/3
-2/3: b - 14/9= 5/3
-2/3: b = 5/3+ 14/9
-2/3: b= (5•3)/(3•3) + 14/9
-2/3: b= 15/9+ 14/9
-2/3 : b= 29/9
-2/3: 29/9= b
-2/3• 9/29= b
-2/1• 3/29= b
b= -6/29
Проверка
-2/3: -6/29 - 1 5/9= 2/3• 29/6 - (9•1+5)/9= 1/3• 29/3 - 14/9= 29/9 - 14/9= 15/9= 1 6/9= 1 2/3
3))) (-4,2: 2,8) :t= 0,5 : 7 2/3 : 3/23
(-1,5):t = 0,5: (7•3+2)/3 • 23/3
(-1,5):t= 1/2: 25/3• 23/3
(-1,5):t= 1/2• 3/25• 23/3
(-1,5):t= 1/2• 1/25• 23/1
(-1,5):t= 23/50
(-1,5) : 23/50= t
(-15/10)• 50/23= t
(-15/1)• 5/23=t
t= - 75/23= -3 6/23
Проверка
(-4,2:2,8): -75/23= 0,5:7 2/3 :3/23
(-1,5)• (-23/75)= 1/2• 3/25• 23/3
15/10• 23/75= 69/150
1/10• 23/5= 23/50
23/50= 23/50
4))) {7/8 : (-2 1/4) :5/6 : (-2 1/2) } :с= -0,24
{7/8: ( - (2•4+1)/4 ) • 6/5 : ( - (2•2+1)/2) }:с= -0,24
{ 7/8: (-9/4)• 6/5 : (-5/2)}:с=-0,24
{7/8• 4/9• 6/5• 2/5}: с=-0,24
{7/2• 1/3• 2/5• 2/5}:с= -0,24
{7/1• 1/3• 1/5• 2/5}: с= -24/100
14/75: с= -6/25
14/75: -6/25= с
14/75• -25/6=с
7/3• -1/3=с
С= -7/9
Проверка
{7/8 : (-2 1/4) :5/6: (-2 1/2) }: -7/9=
{7/8• 4/9• 6/5• 2/5} • -9/7=
{7/1• 1/3• 2/5• 1/5}• -9/7=
14/75• -9/7= 2/75• -9/1= -18/75= -6/25= -(6:25)= -0,24