a) 27,42 + 51,24 + 22,58 - 28,76

= 51,24 + 28,76 - 27,42 + 22,58

= 80 - 50 

= 30

b) 28,67 x 99 + 28,67

= 28,67 x 99 + 28,67 x 1 

= 28,67 x ( 99 + 1 )

= 28,67 x 100

= 2867

^ - ^

a,27,42+51,24+22,58-48,76

=(27,42+22,58)+(51,24-48,76)

=50+2,48

=52,48

b,28,67x99+28,67

=28,67x99+28,67x1

=28,67x(99+1)

=28,67x100

=2867

a) 27,42+51,24+22,58-28,76

=27,42+22,58-51,24+28,76

=50+80=130

b) 28,67x99+28,67

=28,67x99+28,67x1

=28,67x(99+1)

=28,67x100=2867

a, 27,42 + 51,24 + 22,58 + 48,76

= ( 27,42 + 22,58 ) + ( 51,24 + 48,76 )

= 50 + 100

= 150

b, 28,67 x 99 + 28,67

= 28,67 x ( 99 + 1 )

= 28,67 x 100

= 2867

a)   \(\text{27,42 + 51,24 + 22,58 + 48,76}\)

    \(=\left(27,42+22,58\right)+\left(51,24+48,76\right)\)

    \(=50+100\)

    \(=150\)

b)  \(\text{28,67 x 99 + 28,67}\)

    \(=28,67\cdot99+28,67\cdot1\)

    \(=28,67\cdot\left(99+1\right)\)

    \(=28,67\cdot100\)

     \(=2867\)

a) 27,42+51,24 + 22,58+48,76

 =  (27,42+22,58)+ (51,24+48,76)

  = 50+100

  = 150

b) 28,67 x 99 + 28,67 

= 28,67 x 99 + 28,67 x 1

= 28,67 x ( 99 + 1 )

=28,67 x 100 = 2867

45,6 x 99 + 45,6 

= 45,6 x 99 + 45,6 x 1

= 45,6 x ( 99+ 1 )

= 45,6 x 10

= 456

45,6 x 99 + 45,6

= 45,6 x 99 + 45,6 x 1

= 45,6 x (99 + 1)

= 45,6 x 100

= 4560

trong bai toan cua em dau co 1 dau a

a , 72 , 9 * 99 + 72 + 0 , 9

= 72 , 9 * 99 + 7 2 , 9

= 72 , 9 * ( 99 + 1 )

= 72 , 9 * 100

= 7290

a , 0 , 8 * 96 + 1 , 6 * 2

= 0 , 8 * 96 + 0 , 8 * 2 * 2

= 0 , 8 * 96 + 0 , 8 * 4

= 0 , 8 * ( 96 + 4 )

= 0 , 8 * 100

= 80

a. 7290

b. 80

MINH Edogawa Conan

= (( 7,5 + 26,4 ) x 18,3 ) x ( 4,7 x 11 - 47 x 10 - 47 ) 

= ( 33,9 x 18,3 ) x ( 4,7 x ( 11 - 10 - 1) 

= 620,37 x 0 

= 0

( 7,5 x 18,3 + 26,4 x 18,3 ) x ( 47 x 11 -4700 x 0,1 - 47)

= (( 7,5 + 26,4 ) x 18,3 ) x ( 47 x 11 - 47 x 10 - 47)

= ( 33,9 x 18,3) x (( 11 - 10 - 1 ) x 47 )

= 620,37 x ( 0 x 47)

= 620,37 x 0

= 0

Chúc bạn học tốt !

\(\dfrac{1}{3}+\dfrac{6}{5}-\dfrac{1}{5}+\dfrac{2}{3}=2\)

1/3+6/5−1/5+2/3=2

SSH: ( 99 - 1 ) : 2 + 1 = 50

Tổng: ( 1 + 99 ) . 50 : 2 = 2500

Ta thấy : 1 + 99 = 2 + 58 = .... = 100

Số cặp từ 1 đến 99 là : 100 : 4 = 25 (cặp số)

Suy ra : Tổng = 100 x 25 = 2500

15,42 x 139,2- 15,42 x 129,2 = 15,42 x (139,2 - 129,2 )

                                               = 15,42 x 100

                                               = 1542

15,42 x 139,2- 15,42 x 129,2

=15,42x(139,2-129,2)

=15,42x10

=154,2

=5.032,74

NHỚ K MÌNH NHA

45,34 x 111

= 45,34 x ( 100 + 10 + 1 )

= 45,34 x 100 + 45,34 x 10 + 45,34 x 1

= 4534 + 453,4 + 45,34

= 5032,74

Hok tốt ! ^_^