e)=4pe30-9pe30=-5pe30=-1pe6
f)=1\4 (amplificam prin 5)+2\5(amplificam prin 4)=5\20+8\20=13\20
g)-3/7(amplificam cu 3)-20/21(amplificam cu 1)=9/21+(-20/21)=-29/21
h)5/6(amplific cu 8)-3/8(amplif ci 6)=45/48-18/48=9/24³=3/8
i)=¹37/12-(-²1/6)=37/12+(-2/12)=35/12