Dễ :v tự làm đy..........

1 ) ( 6x 8 - 48 ) : ( 10 + 11 + 12 + 13 + 14 )

= ( 48-48 ) : ( 10+11+12+13+14)

= 0 x ( 10 + 11 + 12 + 13 + 14 )

= 0

2  ) 16 x 8 + 16 x 2

= 16 x ( 8 + 2)

= 16 x 10

= 160

1)  (6 x 8 - 48) :(10 + 11 + 12 + 13 + 14 )

=(48-48):(10 + 11 + 12 + 13 + 14 )

=0:(10 + 11 + 12 + 13 + 14 )

=0

2)  16 x 8 + 16 x 2

=16x(8+2)

=16x10

=160

K nha

2. Tính (+5) + ( +4) = 9

3.Tính (- 9) + ( - 1) = -10

4.Tính : 28 + (-15) = 13

5.Tính (-15) + 12 = - 3

6.Tính (-25) + 25 = 0

7.Tính : 13 - 17 = - 4

8.Tính : (-78) - 9 = - 87

9.Tính : ( -24) - ( - 16) = - 8

10.Tính : 17 - (-3) = 20

11.Tính nhanh : (-21) - ( 48 + 52 - 21) = -100

2,  (+5)+(+4)=+9 hoạc 9 cũng được

3,  (-9)+(-1)=-10

4,  28+(-15)=13

5,  (-15)+12=-3

6,  (-25)+25=0

7,  13-17=4

8,   (-78)-9=-87

9,  (-24)-(-16)=-40

10, 17-(-3)=20

11,  (-21+21)-(48-52)=-4

2.  (+5) + ( +4) = 9

3. (- 9) + ( - 1) = -10

4. 28 + (-15) = 13

5. (-15) + 12 = - 3

6. (-25) + 25 = 0

7. 13 - 17 = - 4

8. (-78) - 9 = - 87

9.( -24) - ( - 16) = - 8

10. 17 - (-3) = 20

11. (-21) - ( 48 + 52 - 21) = -100

a ) 45 kg x 2 + 45 kg + 45 kg x 2 + 45 kg x 2 + 45 kg x 3

= 45 kg x 2 + 45 kg x 1 + 45 kg x 2 + 45 kg x 2 + 45 kg x 3

= 45 kg x ( 2 + 1 + 2 + 2 + 3 )

= 45 kg x 10

= 450 kg

b ) 16 x 48 + 8 x 48 + 16 x 48

= ( 16 + 8 + 16 ) x 48

= 40 x 48

= 1920

a)
\(\frac{1.2+2.4+3.6+4.8+5.10}{3.4+6.8+9.12+12.16+15.20}\)
\(\frac{2.3\left(1.2\right)+2.3\left(2.4\right)+2.3\left(3.6\right)+2.3\left(4.8\right)+2.3\left(5.10\right)}{3.4\left(3.4+6.8+9.12+12.16+15.20\right)}\)
\(=\frac{\left(3.4+6.8+9.12+12.16+15.20\right)}{2.3\left(3.4+6.8+9.12+12.16+15.20\right)}=\frac{1}{2.3}=\frac{1}{6}\)

 

A) 137/ 12

B) 4

C) 5

b, 3/5 + 4/7 + 2/8 + 10/25 + 9/21 + 28/16

= 3/5 + 4/7 + 2/8 + 2/5 + 3/7 + 14/8

= (3/5 + 2/5) + ( 4/7 + 3/7) + ( 2/8 + 14/8)

= 1 + 1 + 7/4

= 2 + 7/4 = 15/4

c , 8/7 + 7/6 + 5/8 + 10/12 + 24/28 + 6/16 

= c , 8/7 + 7/6 + 5/8 + 5/6 + 6/7 + 1/2

= (8/7 + 6/7) + (7/6 + 5/6) + 5/8 + 1/2

= 14/7 + 12/6 + 5/8 + 1/2

= 2 + 2 + 5/8 + 1/2

= 4 + 9/8 = 41/8

\(\frac{33496}{3}\)

\(\frac{49^{24}.125^{10}.2^8-5^{30}.7^{49}.4^5}{5^{29}.16^2.7^{48}}\)

\(=\frac{\left(7^2\right)^{24}.\left(5^3\right)^{10}.2^8-5^{30}.7^{49}.\left(2^2\right)^5}{5^{29}.\left(2^4\right)^2.7^{48}}\)

\(=\frac{7^{48}.5^{30}.2^8-5^{30}.7^{49}.2^{10}}{5^{29}.2^8.7^{48}}\)

\(=\frac{7^{48}.5^{30}.2^8.\left(1-7.2^2\right)}{5^{29}.2^8.7^{48}}\)

\(=5.\left(1-7.4\right)\)

\(=5.\left(1-28\right)\)

\(=5.\left(-27\right)=-135\)

8 x 2 = 16       8 x 3 = 24       8 x 4 = 32       8 x 5 = 40

16 : 8 = 2       24 : 8 = 3       32 : 8 = 4       40 : 8 = 5

8 x 6 = 48       8 x 7 = 56       8 x 8 = 64       8 x 9 = 72

48 : 8 = 6       56 : 8 = 7       64 : 8 = 8       72 : 8 = 9

16                         24                       32                 40

2                           3                        4                      5

48                         56                       64                   72

6                           7                         8                     9