571
а. (3/16=1/4)*8= (3/16+4/160*8=7/16 *8=14
(5/9+2/3):11= (5/9=6/9):11=11/9 :11=1/9
(7/8-5/24)*48=(21/24-5/24)*48=16/24 *48=32
(9/13-9/39):9= (27/39-9/39):9=18/39 :9=2/39
(4/15-1/5)*25= (4/15-3/15)*25=1/15*25=5/3= 1 2/3
(7/12+5/36):13= (21/36+5/36):13= 26/36 :13= 2/36=1/18
548
(6-3 5/12) -(3-11/12)= (5 12/12 -3 5/12)- (2 12/12-11/12)=2 7/12-2 1/12=6/12=1/2
(5 - 2 7/19)- (4-3 2/19)= (4 19/19-2 7/19)- (3 19/19-3 2/19)=2 12/19-12/19=2
(7-3 7/11) - (4-2 3/11)=(6 11/11- 3 7/11)-(3 11/11-2 3/11)=3 4/11-1 8/11=2 15/11-1 8/11=1 7/11
(8 -4 13/20)-(6-5 3/20)= (7 20/20-4 13/20)- (5 20/20- 5 3/20)= 3 7/20-17/20= 2 27/20-17/20= 2 10/20= 2 1/2