( 5 × a + 3 ) × 4 - 32 = 100
( 5 × a + 3 ) × 4 = 100 + 32
( 5 × a + 3 ) × 4 = 132
5 × a + 3 = 132 : 4
5 × a + 3 = 33
5 × a = 33 - 3
5 × a = 30
a = 30 : 5
a = 6 → numarul, aflat prin metoda mersului invers
Verific:
( 5 × 6 + 3 ) × 4 - 32 = 100
= 33 × 4 - 32 =
= 132 - 32 =
= 100
