1.Tính hợp lý
1/35.18-5.7.28
2/45-5.(12+9)
3/29.(19-13)-19.(29-13)
4/(-12).47+(-12).52+(-12)
5/2575+37-2576-29
Giúp mik vs
1.Tính hợp lý
1/35.18-5.7.28
2/45-5.(12+9)
3/29.(19-13)-19.(29-13)
4/(-12).47+(-12).52+(-12)
5/2575+37-2576-29
Giúp mik vs
1.
$35.18-5.7.28$
$=35.18-(5.7).28$
$=35.18-35.28$
$=35.(18-28)$
$=35.(-10)$
$=-350$
2.
$45-5.(12+9)$
$=45-45-60$
$=-60$
3.
$29.(19-13)-19.(29-13)$
$=29.6-19.16$
$=174-304$
$=-130$
4.
$(-12).47+(-12).52+(-12)$
$=(-12).(47+52+1)$
$=(-12).100$
$=-1200$
Đáp án: 1. -350
2. -60
3. -130
4. -1200
Giải thích các bước giải:
1. 35.18-5.7.28
= 35.18-35.28
= 35.(18-28)
= 35.(-10)
= -350
2. 45-5.(12+9)
= 45-5.12-5.9
= 45-60-45
= (45-45)-60
= 0-60
= -60
3. 29.(19-13)-19.(29-13)
= 29.19-29.13-19.29+19.13
= (29.19-19.29)+(19.13-29.13)
= 0+(19.13-29.13)
= 19.13-29.13
= 13.(19-29)
=13.(-10)
=-130
4. (-12).47+(-12).52+(-12)
= (-12).47+52+1
= -12.100
= -1200