Đáp án:
Giải thích các bước giải:
16/. (-25)(75 -45) - 75(45 -25) = -25.75 + 75. 25
= ( -25.75 + 75. 25 ) + (25. 45 - 75. 45)
= 0 + 45.(25 - 75) = 45.(- 50) = - 2250
17/ .(-37 - 17).(-9) + 35. (-9 -11)
=(-54).(-9) + 35.(-20) = 486 - 700 =-214
18/. (187 - 23) - (20 -180) = 164 - (-160) = 324
19/. 512.(2 - 128) - 128. (-512)
= 512.(2 - 128 + 128)= 512. 2 = 1024
20/. 17. (-25) + 25. 21 = 25.(-17 + 21) = 25 .4 = 100
21/. 160 : {|-17| + [32 . 5 - (14 + 211 : 28 )]}
= 160 : { 17 + [9. 5 - (14 + 23 ]}
= 160 : { 17 + [45 - (14 + 8)] = 160 : { 17 + ( 45 - 22)}
= 160 : (17 +23) = 160 : 40 = 4
22/.16.(38 - 2) - 38.(16 - 1) = 16 . 38 - 16. 2 - 38. 16 + 38.1
= (16 . 38 - 38. 16) - 16. 2 + 38.1 = 0 - 32 + 38 = 6
23/. |-6| + (-7) + |-4| + (-3)
= 6 - 7 + 4 - 3 = (6 + 4) - (7 + 3) = 10 - 10 = 0
24/. 26.(-125) - 125.(-36)
= -125 .( 26 - 36) = -125 . (-10) = 1250
25/. 56 : 53 - 50 .51 .52
= 56-3 - 50 +1+2 = 53 - 53 = 125 - 125 = 0
26/. 125.(-24) + 24 . 225 = 24 .(-125 + 225) = 24 . 100 = 2400
27/. 21. 135 + 21 .65 - 200
= 21.(135 + 65) - 200 = 21. 200 - 200. 1 = 200. (21 - 1)
= 200 .20 = 3000
28/.42 + (-19) + 58 - (-19)
= 42 - 19 + 58 + 19 = (- 19 + 19) + (42+ 58) = 0 + 100
= 100
29/. 100 : {31 - [24 : (18 -7.2 ]}
= 100 : {31 - [24 : (18 - 14)]} = 100 : {31 - (24 : 4)}
= 100 : ( 31 - 6) = 100 : 25 = 4
30/. 23 .5 - 32 . 4 + 4 . 6
= 8.5 - 9.4 + 4.6 = 4.(5 . 2 - 9 + 6) = 4. 7 = 28
