Bonjour
a. 1 + 2/7 = (1 x 7) / (1 x 7) + 2/7 = 7/7 + 2/7 = 9/7
b. 5 : 2/7 = 5 x 7/2 = 35/2
c. 2 * 2/7 : (- 3/4) = 4/7 x (- 4/3) = - 16/21
d. - 3/4 : (- 3) * 5 = - 3/4 x (- 1/3) * 5 = 3/12 * 5 = 15/12 = 5/4
e. 1/5 - 1 : (- 3/4) = 1/5 - 1 x (- 4/3) = 1/5 + 4/3 = 3/15 + 20/15 = 23/15
f. (5 + 2/7) : (- 3/4)
= [(5 x 7) / (1 x 7) + 2/7] x (- 4/3)
= (35/7 + 2/7) x (- 4/3)
= 37/7 x (- 4/3)
= - 148/21
g. 2/7 : (- 3/4 - 5)
= 2/7 : [- 3/4 - (5 x 4) / (1 x 4)]
= 2/7 : (- 3/4 - 20/4)
= 2/7 : (- 23/4)
= 2/7 x (- 4/23)
= - 8/161
