: 1 ) ;
2) .
3) ;
4) ;
5)
1.
2.
3.
4.
() 8, 6, 5*, 2.
2. : ; ( 91).
5*. 1) 5 , , (24 ) 6 ; 4 . 4 , , 4 ().
2) 6 .
6. + 27 > 50 (24, 25, 26,...);
+ 13>40 (28, 29, 30,...);
∙ 7 > 100 (15, 16, 17,...);
∙ 7 < 100 (14, 13, 12,..., 0).
8. (17- 7): 5 = 2; 40-10 ∙ 2 =20;
(23+ 4): 3 = 9; 42-21 ∙ 2 = 0.
5.
() 1, 3, 4, 7.
1. . , 623: 76,
(6 < 76, 62 < 76);
( ) 62 8 ( 62 7);
7: 76 7 = 532, 623 - 532 = 91, 91 > 76.
7 , ;
8: 76 8 = 608, 623 - 608 = 15, 15<76.
8 .
3. . : . 27 , , 18 . 5 . , ?
1) 27 + 18 = 45 () ;
2) 45: 5 = 9 (/) ;
3) 27: 9 = 3 () ;
4) 5-3 = 2 () .
7.
) : 15 = 87, = 1305; ) : 240 = 12, = 2880.
) 9, 10.
9.
(800 - 480): 2 = 160 (/) ;
800: 160 = 5 (); 480: 160 = 3 ().
7.
8.
114
. .
: 1) ;
2) .
3) ;
4) ;
5)
1.
2.
3.
4.
() 7, 6*.
6*. 5 5 5 - 5 5 = 100.
7. 2400: 10: 2 = 2400: (10 2)
1560:3 ∙ 10>1560: (3 ∙ 10)
|
|
|
68 40 = 68 (4 10)
54 ∙ 50 > 54 ∙ (10: 5)
5.
() 1, 4, 2, 5, 3, 8.
1. . , . : 264: 12. 26 , 26: 12 , 2:1 2, : 12 2 = 24, 26 - 24 = 2; 2 < 12, 2 . 2 . + 4 . = 24 .; 24: 12 2 . .
2. :
?
,
, 4. , 4 . ( , .)
4.
 |
1) 620: 5 = 2124 () ;
2) 10 620 + 2124 = 12 744 () ;
3) 12 744: 4 = 3186 () .
8. 97 8 = 776.
 |
)9, 10.
9.
2 , :
? ?
.
7.
8.
115
