13.1)х:12=4.3/4:7.1/8
х:12=19/4:57/8
х=19/4*12:57/8
х=57:57/8
х=57*8/57
х=8
2)6.1/2:х=6.5/6:4,1
х=6.1/2*4,1:6.5/6
х=13/2*4,1:41,6
х=53,3/2:41/6
х=53,3/2*6/41
х=159,9/41
х=3,9
3)3.1/3х:1,5=4.2/7:3/14
10/3х:1,5=30/7:3/14
10/3х=1,5*30,7:3/14
10/3х=15,35:3/14
10/3х=15,35*14/3
10/3х=214,9/3
10/3х=71,63
х= 71,63:10/3
х=71,63*3/10
х=21,489
4)3.7/19:1.1/2=2.3/8:0,8х
64/19:3/2=2:0,8х
0,8х=2*3/2:64/19
0,8х=3:64/19
0,8х=3*19/64
0,8х=19/21,3
х=19/21,3:0,8
х=19/21,3*1/0,8
х=23,75/21,3
14.1)22-2,98*0,2:0,4-2,1+3,6=24,99
1.-2,98*0,2=-0,596
3.-0,596:0,4=-1,49
4.22+1,49=23,49
5.23,49-2,1=21,39
6.21,39+3,6=24,99
2)21,585-0,585-18,009:3:0,9+0,869*10=36,36
1.-18.009:3=-6,003
2.-6,003:0,9=-6,67
3.21,585-0,585=21
4.21+6,67=27,67
5.0,869*10=8,69
6.27,67+8,69=36,36
3)0,79*71-31,45:0,85+3,8*10,14:7,8=24.03
1.0,79*71=56,09
2.31,45:0,85=37
3.56,09-37=19,09
4.3,8*10.14=38,532
5.38,532:7,8=4,94
6.19.09+4,94=24.03
4)3,13(36,599+4,026-8,545-0,08):4=25,04
1.36,599+4,026=40,625
2.40.625-8,545=32.08
3.32.08-0,08=32
5.3,13*32=100.16
6.100.16:4=25.04
5)23-0,05*10.1+0,395:(49,001-49)*0,009=27.06
1.-0,05*10.1=-0,505
2.49,001-49=0,001
3.0,395:0,001=395
4.395*0,009=3,555
5.23+0,505=23,505
6.23,505+3,555=27.06
6)176(1,866+3.134-3,77):(15,481+1,2-8,681)=27,06
1.1,866+3.134=5
2.5-3,77=1.23
3.176*1,23=216,48
4.15,481+1,2=16.681
5.16.681-8,681=8
6.216,48:8=27,06
7)21-0,2(92,28-91)+73.26:(10,45-0,45)=28.07
1.92,28-91=1,28
2.0,2*1,28=0,256
3.21-0,256=20.744
4.10.45-0.45=10
5.73.26:10=7.326
20,744+7,326=28,07
8)35,628+2,372-316,66:0.5:(99,479-284,79*0,1)=33.06
1.-316,66:0,5=-633,32
2.-284,79*0,1=-28,479
3.99,479+28,479=127,958
4.-633.32:127,958=4,94
5.35,628+2,372=38
6.38-4,94=33.06
15)1)(15/16-2,25)*0,16-0,42:0,4=1.246875
1.15:16-2,25=-1,3125
2.-1,3125*0,15=-0,196875
3.-0,42:0,4=-1.05
4.-0.196875+1,05=1.246875
2)-0,168:1,6+0,2(0,45-4/5)=0.035
1.-0.168:1,6=-0,105
2.0,45-4/5=-0,35
3.0,2*(-0,35)=-0,07
4.-0.105-0.07=0.035
3)-0,54(-1/9):(4,59:4,5-1,5)-2=-1,875
1.-0,54*(-1/9)=-0,06
2.4,59:4,5=1.02
3.1.02-1,5=-0,48
4.-0,06:(-0,48)=0.125
5.0,125-2=-1,875
4)-3+(2,94:2,8-1,5)(-1/9):(-0,036)=-4.38
1.2,94:2,8=1.05
2.1,05-1.5=-0,45
3.-0,45*(-1/9)=0,05
4.0,05:(-0,036)=-1.38
5.-3-1.38=-4,38
5)(0,02*0,01-0,01):0,25-3/8=-0,3358
1.0,02*0,01=0,0002
2.0,0002-0,01=-0,0098
3.-0,0098:0,25=-0,0392
4.-0,0392-3/8=-0.3358
6)-3/4+8,5(0,021:0,01-2,51)=2,735
1.0.021:0.01=2.1
2.2.1-2.51=-0,41
3.8,5*(-0,41)=-3.485
4.-3/4+3,485=2,735
7)(0,15-0,15*6,4):(-3/8+0,175)=-5.55
1.-0,15*6,4=-0,96
2.0,15+0,96=1.11
3.-3/8+0.175=-0,2
4.1.11:(-0,2)=-5.55
8)(1,6*2,15-0,23):(3,45-3.3/4)=16,05
1.1,6*2.15=3.44
2.3,44-0,23=3.21
3.3.45-3.3/4=3.45-15:4=0,2
4.3.21:0,2=16.05