Ответы и объяснения

2013-11-22T11:56:31+00:00
№ 1
35/42=5/6
70/84=35/42=5/6
84/56=42/28=6/4=1 2/4=1 1/2

№2
3/16<5/24
13/330>9/220

№3
7/8-5/6=(21-20)/24=1/24
13/16+7/24=(156+56)/192=212/192=53/48
19/20-5/12-2/5=(57-25-24)/60=8/60=2/15

№4
3 5/8+1 2/3=29/8+5/3=(87+40)/24=127/24=5 7/24
4 4/9-2 5/6=40/9-17/6=(80-51)/18=29/18=1 11/18
6 7/12+(5 3/40-4 8/15)=79/12+(203/40-68/15)=(790+609-544)/120=855/120=57/8=7
1/8

№5
5  4/5+5 4/5+1 1/2=29/5+29/5+3/2=(58+58+15)/10=131/10=13 1/10

№6
1 1/8*9 1/3=9/8*28/3=21/2=10 1/2
3/4*8/9=2/3
3/10*2 6/7*1 5/9=3/10*20/7*14/9=20/3=6 2/3

№7
6/29*(6-2 3/11*1 2/9)=2/3
2 3/11*1 2/9=25/11*11/9=25/9
6-25/9=6/1-25/9=(54-25)/9=29/9
6/29*29/9=2/3