Em tự đặt tính nhé     69:3=23     86:2=43

69; 3 = 23

86; 2 = 43

tự đặt tính đi nhá:

69:3=23.

86:2=43.

\(\left(2\frac{1}{3}+3\frac{1}{2}\right):\left(x+3\frac{1}{7}\right)+7\frac{1}{2}=1\frac{69}{86}\)

\(\left(\frac{7}{3}+\frac{7}{2}\right):\left(x+\frac{22}{7}\right)+\frac{15}{2}=\frac{155}{86}\)

\(\left(\frac{14}{6}+\frac{21}{6}\right):\left(x+\frac{22}{7}\right)+\frac{15}{2}=\frac{155}{86}\)

 \(\frac{35}{6}:\left(x+\frac{22}{7}\right)=\frac{155}{86}-\frac{15}{2}\)

\(\frac{35}{6}:\left(x+\frac{22}{7}\right)=\frac{155}{86}-\frac{645}{86}\)

 \(\frac{35}{6}:\left(x+\frac{22}{7}\right)=\frac{-245}{43}\)

 \(x+\frac{22}{7}=\frac{35}{6}:\frac{-245}{43}=\frac{35}{6}\cdot\frac{-43}{245}\)

\(x+\frac{22}{7}=\frac{-43}{42}\)

\(x=\frac{-43}{42}-\frac{22}{7}=\frac{-43}{42}-\frac{132}{42}\)

 \(x=\frac{-25}{6}\)

a) \(3^3.38+3.41+3^3.21\)

\(=3\left(3^2.38+41+3^2.21\right)\)

\(=3\left(342+41+189\right)\)

\(=3.527=1716\)

b) \(69.75+25.69-68.10^2\)

\(=69\left(75+25\right)-68.100\)

\(=69.100+68.100\)

\(=100\left(68+69\right)\)

\(=100.137=13700\)

c) \(5^9:5^7+3^{15}:3^{14}\)

\(=5^2+3\)

\(=25+3=28\)

d) \(2^3.17+2^3.39+2^3.24+2^3.20\)

\(=2^3.\left(17+39+24+20\right)\)

\(=8.100=800\)

123,45 + 23,56 +76,44 + 54,55

= (123,45 + 54,55) + (23,56 + 76,44)

= 178 + 100

= 278

456 x 45 + 456 x 10 + - 456 x 55

=456 x (45 +10-55)

=456 x 0

=0

2,5 x 8,5 + 7,5 x 8,5 

=8,5 x (2,5 +7,5)

= 8,5 x 10

= 85

86 x 5 + 86 x 4 + 86

= 86 x (5+4+1)

= 86 x10

860

25 x 8 x 17 x 50

= 50 x 4 x 17 x 50

= 200 x 17 x 50 

= 200 x 50 x 17

= 10000 x 17

= 170000

(12 x 2 + 12 x 4 - 12 x 6 ) : ( 2 + 4 + 6 +... + 12 +14)

=(12 x (2 + 4 - 6) ) : ( 2 + 4 + 6 + ... + 12 + 14 )
= (12 x 0 ) : (2 + 4 + 6 + ... + 12 + 14 )

=0 : ( 2 + 4 + 6 + ... + 12 + 14)

= 0

1) \(373737.73-37.737373\)

\(=37.10101.73-37.73.10101\)

\(=0\)

2) \(19.41414141-41.19191919\)

\(=19.41.1010101-41.19.1010101\)

\(=0\)

3) \(123456.456789456789-456789.123456123456\)

\(=123456.456789.1000001-456789.123456.1000001\)

\(=0\)

4) \(250.12.7\)

\(=250.4.3.7\)

\(=\left(250.4\right).\left(3.7\right)\)

\(=1000.21\)

\(=21000\)

5) \(24.125.9\)

\(=3.8.125.9\)

\(=\left(3.9\right).\left(8.125\right)\)

\(=27.1000\)

\(=27000\)

6) \(125.44.18\)

\(=125.4.11.2.9\)

\(=\left(125.4.2\right).\left(11.9\right)\)

\(=1000.99\)

\(=99000\)

7) \(8.24.6+12.4.52+2.22.24\)

\(=48.24+48.52+48.22\)

\(=48\left(24+52+22\right)\)

\(=48.98\)

\(=48\left(100-2\right)\)

\(=48.100-48.2\)

\(=4800-96\)

\(=4704\)

8) \(18.58.2-9.27.4+12.69.3\)

\(=36.58-36.27+36.69\)

\(=36\left(58-27+69\right)\)

\(=36.100=3600\)

9) \(30.85.3+18.72.5-45.37.2-9.20.10\)

\(=90.85+90.72-90.37-90.20\)

\(=90\left(85+72-37-20\right)\)

\(=90.100=9000\)

bn ơi bn tìm trên google á

coá nhoa bn

S= 4 . 325 . 6 + 4 . 69 .24 + 3 . 399 . 8

S= 4 . 1950 + 4 . 1656 + 4 . 2394

S= 4 . ( 1950 + 1656 + 2394 )

S= 4 . 6000

S= 24000

1. (-34)+24+(-7)+27=-10+20=10

2.99+(-100)+101=(99+101)+(-100)=200-100=100

3.(-75)+69+(-25)+131=(69+131)-(75+25)=200-100=100

1) \(\left(-34\right)+24+\left(-7\right)+27\)

\(=-34+24-7+27\)

\(=-\left(34-24\right)-7+27\)

\(=-10-7+27\)

\(=-\left(10+7\right)+27\)

\(=-17+27\)

\(=27-17\)

\(=10\)

2) \(99+\left(-100\right)+101\)

\(=99-100+101\)

\(=-100+99+101\)

\(=-\left(100-99\right)+101\)

\(=-1+101\)

\(=101-1\)

\(=100\)

3) \(\left(-75\right)+69+\left(-25\right)+131\)

\(=-75+69-25+131\)

\(=-\left(75-69\right)-25+131\)

\(=-6-25+131\)

\(=-\left(6+25\right)+131\)

\(=-31+131\)

\(=131-31\)

\(=100\)

1. (-34) + 24 + (-7) + 27

= (-10) + 20

=10

2. 99 + (-100) +101

= (-1) + 101

=100

3. (-75) + 69 + (-25) + 131

= (-6) + (-25) +131

= (-31) + 131

= 100

=