Задача:
Решил – 12 пр.
Осталось- 24 пр.
? пр.
12 + 24 =
10
2
20
4
( 10 + 20 ) +
(2 + 4 ) =
36 ( примеров )
Ответ : всего 36 примеров
58 + 31 =
50
8
30 1
( 50 + 30 ) +
( 8 + 1 ) =
89
41 + 36 =
40
1
30
6
( 40 + 30 ) + ( 1 + 6 ) =
77
89 – 65 =
80
9
60
5
( 80 – 60 )
+ ( 9 – 5 )
12 + ( 20 + 30 ) – 2 =
= 24
10 2
12 + 50 – 2 =
= (10 + 50 ) + (2 – 2)=
60 + 0 =
4 + 6 + ( 45 – 5 ) =
(4 + 6) +
40 =
65 – 30 + ( 20 – 10 ) =
65–30 + 10 =
35 + 10 = 45
(97 – 7 ) – ( 35 – 5) =
90 – 30 =