Si vous pouriez m’aider ça serait super gentil je n’y arrive pas

A = 13/21
B= 2/3
C= 8/7
D= -1/4
E= 1
F= 1
G= 70/10

a.3/7 +4/21
= 3X3/7X3 +4/21
=9/21+4/21
=13/21

b.-1/3+1
= 1-1/3
= 2/3

c.1/2+1/4+1/8
=1X4/2X4+1X2/4X2+1/8
=4/8+2/8+1/8
=7/8

d.5/12-2/3
=5/12-2X4/3X4
=5/12-8/12
=-3/12

e.1X8X3
———
2X6X2

=1X2X2X2X3
—————
2X2X3X2

=1

f.-5/2X(-2/3)X3/5
=5/3X3/5
=1

g.(-2)X5X(-4)X3X7X(-5)
————————————
-10X6

= (-2)X5X(-2)X2X3X7X(-5)
————————————
-2X5X3X2

=-2X7X(-5)
—————
1


a.3/10
b.3X5X3X7
—————
7X7X5X5
=9/35
c.2X3X2X3X2X2X2X3
——————————
2X4X2X2X2X3X2X5
=3X3
—————
4X2X5
=9/40
d.11X5X4X2X3
———————
4X2X4X11X3
=5/4

a.2/15+2/5
=2/15+2X3/5X3
=2/15+6/15
=8/15

b.3/4+5/4
=8/4
=2/1

c.5/2-21/10
=5X5/2X5-21/10
=25/10-21/10
=4/10
=2/5