(5/7-1/3)+(1/4-1/5)+0,25

ой

1/20+25/100=30/100=3/10

(5/7-1/3)+(1/4-1/5)+0,25=(15/21-7/21)+(5/20-4/20)+0,25 =8/21-1/20+0,25=8/21+4/20=244/420=61/105

((5/7)–(1/3))+((1/4)–(1/5))+0,25=((15/21)–(7/21))+((5/20)–(4/20))+0,25=(8/21)+(1/20)+0,25=(160/420)+(21/420)+0,25=(139/420)+0,25=(1390/4200)+(1050/4200)=(340/4200)=(34/420)