31/80+(3/16+39/80) 2/45+(3/45+7/9) (3/75+5/14)+1/14 вычислите используя законы сложения

31/80+(3/16+39/80)=31/80+39/80+3/16=7/8+3/16=14/16+3/16=17/16=1 1/16

2/45+(3/45+7/9)=2/45+3/45+7/9=
1/9+7/9=8/9

(3/75+5/14)+1/14=5/14+1/14+3/75=
3/7+3/75=225/525+21/525=246/525
=82/175