a)(-6*)+(-35)=100
(-6*)=-100-(-35)
(6*)=- 65
(*)=5
b)87+(-4*)=46
(-4*)=46-87
(-4*)=41
(*)=1
c)(-575)+(+2*5)=- 350
2*5=- 350-(-575)
2*5=225
(*)=2
Bài 1. Thay dấu * bởi chữ số thích hợp :
a) (-) + (-35) = -100 ; b) 87 + (-) = 46 ;
c) (-575) + (+) = -350.
thay dau * boi chu so thich hop
*.** =105
Thay dau * boi chu so thich hop de co 517**chia het cho ca ba chu so 6,7,9
thay cac dau * boi cac chu so thich hop de:*1994* chia het cho 99
thay chu a va dau * boi chu so thich hop de aaa x a = ***a
cac chu so o dau * ko nhat thiet phai bang nhau
a, phan tich so 111 ra thua so nguyen to roi tim tap hop cac uoc cua 111.
b, thay dau * boi chu so thich hop:
** . * =111
thay các dau * boi các chu so thich hop de *1994* chia hết cho 99
thay*boi cac chu so thich hop duoi dang hop so.
a. 3*
b. 7*
cac dau *va cac chu boi cac chu so thich hop
a,*8*3x9=70*7*
