100 + 100 : 4 – 50 : 2

= 100 + 25 – 25

= 125 – 25

= 100

17,8 + \(\dfrac{28}{100}\) + 81,2 + \(\dfrac{72}{100}\)

= (17,8 + 81,2) + (\(\dfrac{28}{100}+\dfrac{72}{100}\))

= 99 + \(\dfrac{100}{100}\)

= 99 + 1

= 100

\(17,8+\dfrac{28}{100}+81,2+\dfrac{72}{100}\\ =\left(17,8+81,2\right)+\left(\dfrac{28}{100}+\dfrac{72}{100}\right)\\ =99+\dfrac{100}{100}=99+1=100\)

 4,7 x 1,01 - 4,7 : 100

=4,7 x 1,01 -4,7 x 0,01

=4,7 x (1,01 - 0,01)

=4,7 x1

=4,7

Vậy...........

\(\dfrac{3}{4}+0,75+\dfrac{75}{100}\)

=\(0,75+0,75+0,75\)

=\(0,75\)x\(3\)

=\(2,25\)

3/4 + 0,75 + 75%

=0,75 + 0,75 + 0,75

=0,75 × 3

=2,25

    \(456+627+100+544+373\)

\(=\left(456+544\right)+\left(627+373\right)+100\)

\(=1000+1000+100\)

\(=2100\)

456+627+100+544+373
=(456+544)+(627+373)+100

=1000    +    1000  +  100

= 2100

100:9-79,3:9 

= (100-79,3):9 

=20,7:9

=2,3

`345,6xx1,02-345,6-345,6:100`

`=345,6xx1,02-345,6-345,6xx0,01`

`=345,6xx(1,02-1-0,01)`

`=345,6xx0,01`

`=3,456`

13/50 + 74/100+ 41/100+59/100

[ 13/50 + 74/100 ] + [41/100 + 59/100]

1+1= 2

13/50 + 74% + 41/100 + 0,59

=0,26 + 0,74 + 0,41 + 0,59

=1+1

1

100x(10+10)

100x100=10000

100x(10+10)

=100x20

=2000