a)
|
Calcule en expliquant ton raisonnement. |
4
. 17 = |
4
. (10 + 7) (4 . 10) + (4 . 7) 40 + 28 68 |
4
. (20 - 3) (4 . 20) - (4 . 3) 80 - 12 68 |
2
. (2 . 17) 2 . 34 68 |
|
|||
23
. 6 = |
(20
+ 3) . 6 (20 . 6) + (3 . 6) 120 + 18 138 |
(23
. 3) . 2 46 . 3 138 |
|
|
|||
72
. 11 = |
72
. (10 + 1) 72 . 10 + 72 . 1 720 + 72 792 |
||
|
|||
26
. 9 = |
26
. (10 - 1) 26 . 10 - 26 . 1 260 - 26 234 |
||
|
|||
101
. 27 = |
(100
+ 1) . 27 100 . 27 + 1 . 27 2700 + 27 2727 |
||
|
|||
99
. 57 = |
(100
- 1) . 57 100 . 57 - 1 .57 5700 - 57 5643 |
||
|
|||
28
. 1001 = |
28
. (1000 + 1) (28 . 1000) + (28 . 1) 28000 + 28 28028 |
||
|
|||
17
. 15 = |
(20
- 3) . 15 20 . 15 - 3 . 15 300 - 45 255 |
(10
+ 7) . 15 10 . 15 + 7 . 15 150 + 105 255 |
(17
. 3) . 5 51 . 5 255 |