Bonjour,

1)

3/2 + 4/19 - 5/114 = 190/114

(3 x 57) + (2 x 57) + (4 x 6) / (19 x 6) - 5/114) = 190/114

171/114 + 24/114 - 5/114 = 190/114

190/114 = 190/114.

2)

190 = 2 x 5 x 19

114 = 2 x 3 x 19

3)

190/114

= [(2 x 19) x 5] / [(2 x 19) x 3)]

= (38 x 5) / (38 x 3)

= 5/3.