#1
а) 4 1/4+2 1/3= 4 3/12+2 4/12= 6 7/12
Б) 3- 1 3/8= 2 8/8- 1 3/8= 1 5/8
В) 3 3/4+ 2 4/7= 3 21/28+ 2 16/28= 5 37/28= 5 9/28
Г) 2 4/9- 1 5/6= 2 8/18- 1 15/18= 9/18= 1/2
Д) 7 11/15- (3 9/20+ 1 1/30)= 7 11/15- (4 27+2/60)= 7 11/15- 4 29/60= 7 44/60-4 29/60= 3 15/60= 3 1/4