Răspuns:
a)1/15
b)27/70
Explicație pas cu pas:
a)
2(4/5)*[2(7/10)*(20/63)-(14/15)/(1(3/25))]=
(14/5)*((27/10)*(20/63)-(14/15)/(28/25))=
(14/5)*((27/10)*(20/63)-(14/15)*(25/28))=
(14/5)*((27/10)*(20/63)-(14/15)*(25/28))=
(14/5)*(3*(2/7)-(14/15)*(25/28))=
(14/5)*((6/7)-(1/3)*(5/2))=
(14/5)*((6/7)-(5/6))=
(14/5)*(1/42)=
(1/5)*(1/3)=
1/15
b)((3/4)+(3/5))*(2/7)=
(27/20)*(2/7)=
(27/10)*(1/7)=
27/70
