1.28/10:8,4x48/10-1,3+31/10= 2.22/5+3,75:(3,5-11/6)= 3.5,25x24/7-7,5:27/8= 4.7/3x9/7:3,6+4,375-43/12= 5.2,5:5/3:9/4x4,5-25/9= 6.21/15x26/9-2,7x9/8= 7.36/7x35/9-

1.) 28/10 : 8,4 x 48/10 - 1,3 + 31/10
=28/10 : 84/10 x 48/10 - 13/10 + 31/10
=28/10 x 10/84 x 48/10 - 13/10 + 31/10
=280/840 x 48/10 - 13/10 + 31/10
=1/3 x 48/10 - 13/10 + 31/10
=48/30 - 13/10 + 31/10
=8/5 - 13/10 + 31/10
=16/10 - 13/10 + 31/10
=34/10
=3 4/10
=3 2/5
2.)22/5 + 3,75 : (3,5- 11/6)
=22/5 + 375/100 : (35/10 - 11/6)
=22/5 + 375/100 : (105/30 - 55/30)
=22/5 + 375/100 : 50/30
=22/5 + 375/100 x 30/50
=22/5 + 11.250/5000
=22/5 + 2 1.250/5000
=22/5 + 2 1/4
=4 2/5 + 2 1/4
=4 8/20 + 2 5/20
=6 13/20