dấu nhân là dấu . nha ! (ở THCS)

x.12,3 - x.2,3 = 5,6

x. (12,3-2,3) = 5,6

x. 10         = 5,6

x             = 5,6 : 10

x             = 0,56

( 12,3 x 5) + (5,6 x 2) 

= 61,5 + 11,2

= 72,7

(12,3x5)+(5,6x2)

=61,5+11,2

=72,7.

(12,3x5)+(5.6x2)

=61,5+11,2

=72,7

a,5,6x3,7+5,6x2,3

=5,6x(3,7+2,3)

=5,6x6

=33,6

b,47,85x47-47,85x17

=47,85x(47-17)

=47,85x30

=1435,5

a, 5,6(3,7+2,3)

=5,6x5

=28

b,47,85(47-17)

=47,85x 30

=1435,5

#G2k6#

a) 5,6 x 3,7 + 5,6 x 2,3 

= 5,6 x ( 3,7 + 2,3 )

= 5,6 x 6

=    33,6

b) 47,85 x 47 - 47,85 x 17

= 47,85 x ( 47 - 17 )

=  47,85 x 30

=      1435,5

1) x = 12,3  - 2,3 + 4,5 = 5,5

2) x = 24,4 - 19,44 = 4,96

3) x = 831,6

Nhớ bấm L I K E nhá :)) 

\(1,\)

\(a,1+\frac{1}{3}+\frac{1}{9}+\frac{1}{27}+\frac{1}{81}\)

\(=\frac{81}{81}+\frac{27}{81}+\frac{9}{81}+\frac{3}{81}+\frac{1}{81}\)

\(=\frac{81+27+9+3+1}{81}\)

\(=\frac{121}{81}\)

\(=1\frac{40}{81}\)

\(b,37,25+4,7.2,3-9,8\)

\(=37,25+10,81-9,8\)

\(=38,26\)

\(2,\)

\(a,x:4,37=5,6\left(dư1,53\right)\)

\(x=5,6.4,37+1,53\)

\(\Rightarrow x=26,002\)

\(b,13,5.\left(x:5,6\right)=36,45\)

\(\left(x:5,6\right)=36,45:13,5\)

\(x:5,6=2,7\)

\(x=2,7.5,6\)

\(\Rightarrow x=15,12\)

1.

a . =81/81 + 27/81 + 3/81 + 1/81

    = 112/81

b = 37,52 + 10,81 - 9,8

    = 48,33 - 9,8

     = 38,53

2.   

a .x = 5,6 nhân 4,37 +1,53

    x=24, 472 + 1,53

   x= 26,002

b.  x:5,6=36,45:13,5

x :5,6= 2,7

x=2,7 nhân 5,6

x=15,12 

1.

1+1/3+1/9+1/27+1/81

=81/81+27/81+3/81+1/81

=112/81

b)37,52+4,7*2,3-9,8

=37,52+10,81-9,8

=48,33-9,8

=38,53

2.

a) x:4,37=5,6(dư 1,53)

x=5,6*4,37+1,53

x=26.002

b) 13,5*(x:5,6)=36,45

x:5,6=36,45/13,5
x:5,6=2,7

x=2,7*5,6

x=15,12

K CHO MÌNH NHA

Lời giải:
$(2,41+3,12)\times 2,2=5,53\times 2,2=12,166$

$(5,6-3,21)\times 2,3=2,39\times 2,3=5,497$

$3,276:1,4+7,66=2,34+7,66=10$

$28,886:1,3+77,78=22,22+77,78=100$

a) 5,6x 2 + 2,8 x 4 x 2 +11,2 x 2 -48,5= 11,2 +11,2 x 2 +11,2 x 2 - 48,5 = 11,2 x 5 -48,5 = 56 - 48,5 = 7,5

b) 4,5 x (12,3 + 7,5 +1) = 4,5 x 20,8 = 93,6

a) \(=5,6\cdot\left(4+3+2+1\right)\\ =5,6\cdot10=56\)

b) \(=5\)

a)5,6 x 4 + 5,6 x3 + 5,6 x 2 + 5,6

=5,6x(4+3+2+1)

=5,6x10

=56

b) =5