Đáp án:
Giải thích các bước giải:
a/. 1975 . ( - 115 ) + 1979 . 5
= 1975 . ( - 23 ) .5 + 1979 . 5
= 5. (1975 . -23 + 1979)
= 5.( -45 425 + 1979)
= 5 . (-43 446)
= - 217 230
b/. 153 . 171 - 153 . 77
= 153.(171 - 77)
= 153 . 94
= 14 382
c/. 199 . ( 15 . 17 ) - 199 . ( - 17 + 5 )
= 199 . 255 - 199 . (-12)
= 199.[255 - (-12)}
= 199 . 267
= 53 133
d/. -39 ( 5 - 99) + 99 ( 10 - 39 )
= -39 . 5 + 39 . 99 + 99.10 - 99 . 39
= (39 . 99 - 99 . 39) + (99.10 - 39 .5)
= 39.(99 -99) + (99.2.5 - 39 .5)
= 0 + 5.(99.2 - 39)
= 5. 159
= 795
e/. - 8 : ( -2 ) - 2 . ( - 10 : 2 ) - 7 ( 5 - 4 )
= 4 - 2. (-5) - 7. 1
= 4 + 10 - 7
= 14 - 7
= 7
f/. 7 . [ - 6 : 2 - 15 : ( - 3 ) ] - | - 3 |
= 7 . [ (- 6 : 2) - 15 : ( - 3 ) ] - 3
= 7. [ -3 - (-5) ] - 3
= 7. 2 - 3
= 14 - 3
= 11