2 + 2 × [2 + 2:2 × ( 2 + 2 × 2)] =
2 + 2 × [ 2 + 1 × ( 2 + 4)] =
2 + 2 × ( 2 + 1 × 6)] =
2 + 2 × ( 2 + 6)
2 + 2 × 8 =
2 + 16 = 18