(1,75• 4/7- 1,75: 1 1/8) •4,5- 4,5= -7.___
1)) 1,75• 4/7= 1 75/100• 4/7= 1 3/4• 4/7= (4•1+3)/4 • 4/7= 7/4• 4/7= 1/1• 1/1= 1. 2)) -1 75/100 : 1 1/8= -175/100 : (1•8+1)/8= -7/4 : 9/8= -7/4• 8/9= -7/1• 2/9= -14/9= -1 5/9.
3)) 1- 1 5/9= 1- (1+ 5/9)= -5/9.
4)) -5/9• 4 5/10= -5/9• 4 1/2= -5/9• (4•2+1)/2= -5/9• 9/2= -5/1• 1/2= -5/2= -2 1/2= -2,5.
5)) -2,5- 4,5= -(2,5+4,5)= -7. Или так (-2 5/10)- 4 5/10= -2 1/2 -4 1/2= -5/2 -9/2= -(5+9)/2= -14/2= -7.