3.12:0.25+12.48*3-3.12*6

=3.12*4+3.12*12-3.12*6

=3.12*(4+12-6)

=3.12*10

=31.2

= 3,12 x 4 + 3,12 x 4 x 3 - 3,12 x 6

= 3,12 x 4 +3,12 x 12 - 3,12 x 6

= 3,12 x ( 4 + 12 - 6 )

= 3,12 x 10

= 31,2

2 x 3,12 x 1,25 : 0,25 x 10

= 6,24    x 1,25 x 4     x 10

= 6,24   x        5          x 10

=         6,24  x       50

=             312

12,48 : 0,5 x 6,25 x 4 x 2

= 12,48 x 2 + ( 6,25 x 4 ) x 2

= 12,48 x ( 2 x 2 ) x 25

= 12,48 x ( 4 x 25 )

= 12,48 x 100

= 1248

2 x 3,12 x 1,25 : 0,25 x 10

= 2 x 3,12 x 1,25 x 4 x 10

= 2 x 3,12 x 5 x 10

= ( 2 x 5 ) x 10 x 3,12

= 100 x 3,12

= 312

`3,12:0,25+3,12:0,2+3,12:0,5+3,12xx89`

`=3,12xx4+3,12xx5+3,12xx2+3,12xx89`

`=3,12xx(4+5+2+89)`

`=3,12xx100 = 312`

\(3,12:\dfrac{1}{4}+3,12:\dfrac{1}{5}+3,12:\dfrac{1}{2}+3,12\times89\)

\(=3,12\times4+3,12\times5+3,12\times2+3,12\times89\)

\(=3,12\times\left(4+5+2+89\right)\)

\(=3,12\times100=312\)

3,12:0,25+12,48x3-3,12x6

=3,12:1/4+3,12x4x3-3,12x6

=3,12x4+3,12x12-3,12x6

=3,12x(4+12-6)

=3,12x10

=31,2

\(\frac{1}{7}\cdot\frac{2}{3}+\frac{5}{6}:\frac{3}{10}-\frac{2}{3}\cdot\frac{3}{7}\)

\(=\left(\frac{1}{7}\cdot\frac{2}{3}-\frac{2}{3}\cdot\frac{3}{7}\right)+\frac{5}{6}\cdot\frac{10}{3}\)

\(=\frac{2}{3}\cdot\left(-\frac{2}{7}\right)+\frac{5}{3}\cdot\frac{5}{3}\)

\(=-\frac{4}{21}+\frac{25}{6}=\frac{167}{42}\)

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12 , 48   :   0 , 5   x   6 , 25   x   4   x   2 2   x   3 , 12   x   1 , 25   :   0 , 25   x 10 = 12 , 48   x   2   x   6 , 25   x   4   x   2 2   x   3 , 12   x   1 , 25   x   4   x   10 = 4   x   5   x   2 10 = 4