Давайте рассмотрим выражение (2,5*(6 7/12 - 3 17/36) - 4 1/3 / 0,65) * 27/40 + 2,25.
Преобразуем неправильные дроби:
6
12
7
=6+
12
7
=
12
72
+
12
7
=
12
79
3
17
36
=
3
+
17
36
=
108
36
+
17
36
=
125
36
3
36
17
=3+
36
17
=
36
108
+
36
17
=
36
125
4
1
3
=
4
+
1
3
=
12
3
+
1
3
=
13
3
4
3
1
=4+
3
1
=
3
12
+
3
1
=
3
13
Выполним вычетание дробей:
12
79
−
36
125
=
12⋅3
79⋅3
−
36
125
=
36
237
−
36
125
=
36
112
=
9
28
Умножим результат на 2.5:
2.5
⋅
28
9
=
5
2
⋅
28
9
=
5
⋅
28
2
⋅
9
=
140
18
=
70
9
2.5⋅
9
28
=
2
5
⋅
9
28
=
2⋅9
5⋅28
=
18
140
=
9
70
Выполним деление:
13
3
/
0.65
=
13
3
/
65
100
=
13
3
⋅
100
65
=
13
⋅
100
3
⋅
65
=
1300
195
=
20
3
3
13
/0.65=
3
13
/
100
65
=
3
13
⋅
65
100
=
3⋅65
13⋅100
=
195
1300
=
3
20
Выполним вычитание:
70
9
−
20
3
=
70
9
−
60
9
=
10
9
9
70
−
3
20
=
9
70
−
9
60
=
9
10
Умножим результат на
27
40
40
27
:
10
9
⋅
27
40
=
10
⋅
27
9
⋅
40
=
270
360
=
3
4
9
10
⋅
40
27
=
9⋅40
10⋅27
=
360
270
=
4
3
Прибавим 2.25:
3
4
+
2.25
=
3
4
+
9
4
=
12
4
=
3
4
3
+2.25=
4
3
+
4
9
=
4
12
=3
Ответ: 3