Odpowiedź :
a)
2 i 5/7 + 1 i 3/5 =
= 2 i 25/35 + 1 i 21/35 =
= 3 i 46/35=
= 4 i 11/35
b)
7 i 7/9 - 5 i 1/5 =
=7 i 35/45 - 5 i 9/45=
= 2 i 26/45
c)
5 i 3/8 - 2 i 4/7 =
= 5 i 21/56 - 2 i 32/56=
= 4 i 77/56 - 2 i 32/56=
= 2 i 45/56
d)
9/11 * 13/18 =
= 1/11 * 13/2=
= 13/22
e)
2/7 : 8/21 =
= 2/7 * 21/8=
= 1/1 * 3/4=
= 3/4
f)
3 i 2/5 * 6 i 2/3 =
= 17/5 * 20/3=
= 17/1 * 4/3=
= 68/3=
= 22 i 2/3