4 5/12- 1 1/2 : ( 2 1/6 + 8/15 ) • 1 4/5=
3 5/12.
1)) 2 1/6+ 8/15=2 (1•5)/(6•5)+(8•2)/(15•2)=
2 5/30+ 16/30= 2 21/30= 2 7/10
Сократили 21/30 на 3.
2)) 1 1/2 : 2 7/10 = (1•2+1)/2 : (2•10+7)/10=
3/2: 27/10= 3/2• 10/27=
Сокращаем 3 и 27 на 3; 2 и 10 на 2.
1/1• 5/9= 5/9.
3)) 5/9• 1 4/5= 5/9• (1•5+4)/5=
5/9• 9/5=1/1• 1/1= 1.
сократили 5 и 5 на 5; 9 и 9 на 9.
4)) 4 5/12- 1= 3 5/12.