Voici 5 solutions distinctes :
Solution n°1
8 x 5 = 40
75 / 3 = 25
40 x 25 = 1000
1000 - 1 = 999
Solution n°2
8 x 5 = 40
75 x 40 = 3000
3000 / 3 = 1000
1000 - 1 = 999
Solution n°3
75 x 8 = 600
600 x 5 = 3000
3000 / 3 = 1000
1000 - 1 = 999
Solution n°4
75 x 5 = 375
375 x 8 = 3000
3000 / 3 = 1000
1000 - 1 = 999
Solution n°5
75 x 8 = 600
600 / 3 = 200
200 x 5 = 1000
1000 - 1 = 999