Explications étape par étape:
Ex4
Imaginons
3A=92
3B=3A-5
=92-5
=87
3C=3A+7
=92+7
=99
3D=3C×2
=99×2
=198
3E=3B×3
=99×3
=261
=3A+3B+3C+3D+3E
=92+87+99+198+261
=737
