@ @pbjïØ Üa@ @RR .(400 − 18) + 1 = 383 () 25 . 23 24 () . 25 × 24 × 23 = 13800 () B,C ∈ {0,1,2,…,9} A ∈ {1,2, 3,…, 9} ABCD 1000 < x < 10000 x . D ∈ {0,2, 4, 6, 8} . 9 ×10 ×10 × 5 = 4500 () 97 60 .A ≠ 0 ABCD 3A .4 DC B . 3 × 4 × 4 × 4 = 192