Bonjour
50)
1)
6 ; 12 ; 18 ; 24 ; 30
8 ; 16 ; 24 ; 32 ; 40
2)
a. 7/6 - 9/8 = (7 x 4) / (6 x 4) - (9 x 3) / (8 x 3) = 28/24 - 27/24 = - 3/24 = (3 x - 1) / (3 x 8) = - 1/8
b. - 1/8 + - 5/6 = (- 1 x 3) / (8 x 3) - (5 x 4) / (6 x 4) = - 3/24 - 20/24 = - 23/24.
51)
1)
9 ; 18 ; 27 ; 36 ; 54
12 ; 24 ; 36 ; 48 ; 60
2)
a. - 7/9 + 5/12 = (- 7 x 4) / (9 x 4) + (5 x 3) / (12 x 3) = - 28/36 + 15/36 = - 13/36
b. - 7/12 + 7/9 = (- 7 x 3) / (12 x 3) + (7 x 4) / (9 x 4) = - 21/36 + 28/36 = 7/36.