5/15=1/3
3/12=1/4=0,25
14/35=2/5=0,4
28/42=2/3
10/45=2/9
750/2000=3/8=0,375
243/729=1/3
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сократить:
8*35/49*16=5/7*2=5/14
3*5*42/15*12*21 = 5*2/5*12=1/6
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0.8=4/5
0.24=6/25
0.125=1/8