9の性質
かけ算9の段（9の倍数とその判定法）
- 9 × 1 = 9
- 9 × 2 = 18
- 9 × 3 = 27
- 9 × 4 = 36
- 9 × 5 = 45
- 9 × 6 = 54
- 9 × 7 = 63
- 9 × 8 = 72
- 9 × 9 = 81
- 9 × 10 = 90
- 9 × 11 = 99
- 9 × 12 = 108
- 9 × 13 = 117
- 9 × 14 = 126
- 9 × 15 = 135
- 9 × 16 = 144
- 9 × 17 = 153
- 9 × 18 = 162
- 9 × 19 = 171
- 9 × 20 = 180
- 9 × 21 = 189
- 9 × 22 = 198
- 9 × 23 = 207
- 9 × 24 = 216
- 9 × 25 = 225
- 9 × 26 = 234
- 9 × 27 = 243
- 9 × 28 = 252
- 9 × 29 = 261
- 9 × 30 = 270
- 9 × 31 = 279
- 9 × 32 = 288
- 9 × 33 = 297
- 9 × 34 = 306
- 9 × 35 = 315
- 9 × 36 = 324
- 9 × 37 = 333
- 9 × 38 = 342
- 9 × 39 = 351
- 9 × 40 = 360
- 9 × 41 = 369
- 9 × 42 = 378
- 9 × 43 = 387
- 9 × 44 = 396
- 9 × 45 = 405
- 9 × 46 = 414
- 9 × 47 = 423
- 9 × 48 = 432
- 9 × 49 = 441
- 9 × 50 = 450
- 9 × 51 = 459
- 9 × 52 = 468
- 9 × 53 = 477
- 9 × 54 = 486
- 9 × 55 = 495
- 9 × 56 = 504
- 9 × 57 = 513
- 9 × 58 = 522
- 9 × 59 = 531
- 9 × 60 = 540
- 9 × 61 = 549
- 9 × 62 = 558
- 9 × 63 = 567
- 9 × 64 = 576
- 9 × 65 = 585
- 9 × 66 = 594
- 9 × 67 = 603
- 9 × 68 = 612
- 9 × 69 = 621
- 9 × 70 = 630
- 9 × 71 = 639
- 9 × 72 = 648
- 9 × 73 = 657
- 9 × 74 = 666
- 9 × 75 = 675
- 9 × 76 = 684
- 9 × 77 = 693
- 9 × 78 = 702
- 9 × 79 = 711
- 9 × 80 = 720
- 9 × 81 = 729
- 9 × 82 = 738
- 9 × 83 = 747
- 9 × 84 = 756
- 9 × 85 = 765
- 9 × 86 = 774
- 9 × 87 = 783
- 9 × 88 = 792
- 9 × 89 = 801
- 9 × 90 = 810
- 9 × 91 = 819
- 9 × 92 = 828
- 9 × 93 = 837
- 9 × 94 = 846
- 9 × 95 = 855
- 9 × 96 = 864
- 9 × 97 = 873
- 9 × 98 = 882
- 9 × 99 = 891
- 9 × 100 = 900
9の倍数の判定法
3 の倍数と同様、 9 の倍数かどうかは、各位の数の合計が 9 の倍数かどうかでわかる。例えば
216
という数は 2 + 1 + 6 = 9 であり、 9 は 9 の倍数だから、もとの 216 も 9 の倍数である。
例
5409
5 + 4 + 0 + 9 = 18
↓
18 は 9 の倍数
↓
5409 も 9 の倍数
7695
7 + 6 + 9 + 5 = 27
↓
27 は 9 の倍数
↓
7695 も 9 の倍数
問題
9 × 14 = ( )
9 × 27 = ( )
9 × 18 = ( )
9 × 25 = ( )
9 × 29 = ( )
解答
9 × 14 = 126
9 × 27 = 243
9 × 18 = 162
9 × 25 = 225
9 × 29 = 261
