25.6.4.8.125

=(25.4).(125.8).6

=100.1000.6

=100000.6

=600000

\(25\cdot6\cdot4\cdot8\cdot125\)

\(=25\cdot4\cdot6\cdot8\cdot125\)

\(=100\cdot6\cdot1000\)

\(=100000\cdot6\)

\(=600000\)

\(\infty\)

a) 125 + 70 + 375 + 230 = (125 + 375) + (70 + 230) = 500 + 300 = 800

b) 6² : 4 . 3 + 2 . 5² = 6² : 2² . 3 + 2 . 25 = 3² . 3 + 50 = 3³ + 50 = 27 + 50 = 77

c) 150 : [25 . (18 - 4²)] = 150 : (25 . 2) = 150 : 50 = 3

a: 45+432+155+168

=45+155+432+168

=200+600

=800

b: \(5\cdot135-5\cdot35+175\)

\(=5\cdot\left(135-35\right)+175\)

\(=5\cdot100+175\)

=500+175

=675

c: \(129\cdot172-73\cdot129+129\)

\(=129\cdot\left(172-73+1\right)\)

\(=129\cdot100=12900\)

d: \(29\cdot73+110\cdot71+37\cdot29\)

\(=29\cdot\left(73+37\right)+110\cdot71\)

\(=29\cdot110+71\cdot110=110\cdot100=11000\)

e: \(12:\left\lbrace390:\left\lbrack500-\left(125+35\cdot7\right)\right\rbrack\right\rbrace\)

\(=12:\left\lbrace390:\left\lbrack500-\left(125+245\right)\right\rbrack\right\rbrace\)

\(=12:\left\lbrace390:\left\lbrack500-370\right\rbrack\right\rbrace=12:\left\lbrace\frac{390}{130}\right\rbrace=12:3=4\)

f: \(375:\left\lbrace32-\left\lbrack4+\left(5\cdot9-42\right)\right\rbrack\right\rbrace-14\)

\(=375:\left\lbrace32-\left\lbrack4+45-42\right\rbrack\right\rbrace-14=375:\left\lbrace32-7\right\rbrace-14\)

=375:25-14

=15-14

=1

a) = 217. [(-39) + (-61)]
= 217 . -100
= -21700

trong tích trên có 1 thừa số như thế này:

\(\left(\frac{1}{125}-\frac{1}{5^3}\right)\)

\(=\left(\frac{1}{125}-\frac{1}{125}\right)\)

=0

=> tích trên bằng 0

b/ (-127).57+(-127).43

=(-127)(57+43)

=(-127).10

=-1270

c/ (-13).34-87.34

=34.(-13-87)

=34.(-100)

=3400

a) (-14).(-125).(+3).(-8)

= [(-14).3].[(-125).(-8)]

=     -42  . 1000

=        -42000

b) (-127).57+(-127).43

= -127.(57+43)

= -127.100

=    -12700

c) (-13).34-87.34

= 34.(-13-87)

= 34.(-100)

=  -3400

d) (-25).68+(-34).(-250)

=  - 1700 + 8500

=         6800        ( bài này không cần phải tính hợp lý )

tick nha các bạn yêu quý