a ) 3 / 4 + 5 / 3 =
= 9 / 12 + 20 / 12
= 29 / 12
——————————-
b ) 15 / 7 + 13 / 11 =
= 165 / 77 + 91 / 77
= 256 / 77
———————————
c ) 3 / 13 + 1 / 11 =
= 33 / 143 + 13 / 143
= 46 / 143
———————————-
d ) 16 / 3 + 11 / 37 =
= 592 / 111 + 33 / 111
= 625 / 111
————————————
e ) 11 / 5 + 3 / 7 =
= 77 / 35 + 15 / 35
= 92 / 35
—————————————
f ) 1 / 11 + 5 / 19 =
= 19 / 209 + 55 / 209
= 74 / 209
—————————————
g ) 3 / 5 + 1 / 23 =
= 69 / 115 + 5 / 115
= 74 / 115
