ac=НОД (а; с)·НОК (а; с) = 3·72=216
a=3x
c=3y
НОД(x;y)=1
3x·3y=216
9xy=216 /:9
xy=24
x=3, y=8
a=3·3=9
c=3·8=24
а) 9_5/19 - 7_7/19 + 4_15/19=
= 8 24/19 - 7_7/19 + 4_15/19=
=1 17/19+4 15/19=5 32/19=6 13/19
б) 5_3/28 + 6_25/28 - 7_9/28=
=11 9/28-7 9/29=4
в) 14_5/29 - (5_21/29 + 4_9/29)=
=14_5/29 -9 30/29=14_5/29 -10 1/29=
=4 4/29