Răspuns: x = 10
Explicație pas cu pas:
152 - {5 × [ ( x - 3) : 7 + 47] : 8 + 102} = 20
5 × [ ( x - 3) : 7 + 47] : 8 + 102 = 152 - 20
5 × [ ( x - 3) : 7 + 47] : 8 + 102 = 132
5 × [ ( x - 3) : 7 + 47] : 8 = 132 - 102
5 × [ ( x - 3) : 7 + 47] : 8 = 30
5 × [ ( x - 3) : 7 + 47] = 30 × 8
5 × [ ( x - 3) : 7 + 47] = 240
( x - 3) : 7 + 47 = 240 : 5
( x - 3) : 7 + 47 = 48
( x - 3) : 7 = 48 - 47
( x - 3) : 7 = 1
x - 3 = 1 × 7
x - 3 = 7
x = 7 + 3
x = 10 → numărul, aflat prin metoda mersului invers
