a)  \(6^2:4\times3+2\times5^2\)

\(=36:4\times3+2\times25\)

\(=9\times3+50\)

\(=27+50\)

\(=77\)

b)   \(125+70+375+230\)

\(=\left(125+375\right)+\left(70+230\right)\)

\(=500+300\)

\(=800\)

c)   \(150:\left[25\times\left(18-4^2\right)\right]\)

\(=150:\left[25\times\left(18-16\right)\right]\)

\(=150:\left[25\times2\right]\)

\(=150:50\)

\(=3\)

Cảm ơn bạn nhiều

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

??????????????????????

= (8.125). (25.4).3³

=  1000. 100.9
= 100 000.9
= 900 000

8.4.3^3.125.25

=(8.125).(25.4).27

=1000.100.27

=2100000

a, 125+70+375+230

= (125+375)+(70+230)

= 500+300 = 800

b,  7 2 . 33 + 7 2 . 67

= 49.33+49.67 = 49.(33+67) = 49.100 = 4900

c, 35.11+65.18+35.13+65.6

= 35.(11+13)+65.(18+6) = 35.24+65.24 = 24.(35+65) = 24.100 = 2400

d, 490 – {[(128+22):3. 2 2 ] – 7}

= 490 – {[150:3.4] – 7}

= 490 – {[50.4] – 7}

= 490 – {200 – 7}

= 490 – 193 = 297

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

 49 . 55 + 46 . 49 - 49

=49(55+46)-49

=49.101-49

==> =49.100

   =4900