((3 целых 5\6+2,5)/2,5-(25/36/10/63)-2 целых 3/8))+(1/18*(7/3-3/4)-6 целых 1/3)

((3 целых 5\6+2,5):2,5-(25/36:10/63)-2 целых 3/8))+(1/18*(7/3-3/4)-6 целых 1/3)
=

1)) (3 5/6+ 2,5): 2/5= 3 5/6 :2,5+ 2,5:2,5=
(6•3+5)/6 : 25/10+ 1= 23/6: 5/2+ 1=
23/6• 2/5+ 1= 46/30+ 1= 1 16/30+ 1= 2 16/30= 2 8/15

2)) 25/36 : 10/63=25/36• 63/10= 5/36• 63/2= 5/12•21/2= 5/4• 7/2= 35/8= 4 3/8

{сократили 25 и 10 на 5; 36 и 63 на 3; 12 и 21 на 3)

3)) (2 8/15- 4 3/8 - 2 3/8)= 2 8/15- 6 6/8=
2 (8•8)/(15•8)- 2 (3•15)/(8•15)= 2 64/120- 2 45/120= 19/120

4)) 1/18• (7/3- 3/4)= 1/18• ( (7•4)/(3•4)- (3•3)/(4•3))= 1/18• (28/12- 9/12)= 1/18• 19/12= 19/228= 1/12

5)) 1/12- 6 1/3= = -(6 1/3- 1/12)= -( 6 (1•4)/(3•4) -1/12)= - (6 4/12- 1/12)= -6 3/12= -6 1/4

5)) 19/120 + (-6 1/4)= - 6 1/4+ 19/120= -(6 1/4- 19/120)= - (6 (1•30)/(4•30) -19/120)= - (6 30/120 -19/120)= - 6 11/120