=5+(-5+20)

=5+ 15

=20

(-30)+(- 15)+(-68),

=-(30+ 15+68)

=- 1 13

0+(-3.65)+(+2.75)+(-2.5),

=0-3.65+2.75-2.5

=-3.65+(2.75-2.5)

=-3.65+0.25

=-(3.65-0.25)

=-3.4

(-7 and 2/7)+(+2 and 2/3)+(+4 and 3/7)+(-4 and 1/3),

=(4 3/7-7 2/7)+(2 2/3-4 1/3)

=(-2 6/7)+(- 1 2/3)

=-(2 6/7+ 1 2/3)

=-4 and 1 1/28

(-two thirds)+(half)+(-five sixths)+(-one third),

=-(2/3+ 1/3)+( 1/2-5/6)

=- 1- 1/3

=-( 1+ 1/3)

=- 1 and 1/3

(-four and a half)+{three fifths +(-0. 13)+0.33},

=-(4 1/2-3 2/5)+(0.33-0. 13)

=- 1 and110+0.2

=-( 1 and110-1/5)

=-9/ 10

5+{+4+3+7+(4+5)+6},

=5+4+3+7+9+6

=34