Bonsoir quelqu'un peut m'aider svp . A=(7/8-3)÷(-51/2) B=-5/3+4/49×35/12

A = (7/8 - 3) : (- 51/2)
A = (7 x 3 / 8 x 3 - 3 x 24 / 1 x 24) x - 2/51
A = (21/24 - 72/24) x - 2/51
A = - 51/24 x - 2/51
A =  102/1224
A = 102 x - 1 / 102 x 12
A = - 1/12

B = - 5/3 + 4/49 x 35/12
B = - 5/3 + 140/588
B = - 5 x 196 / 3 x 196 + 140/588
B = - 980/588 + 140/588
B = - 840/588
B = 84 x - 10 / 84 x 7
B = - 10/7