27 と 72
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◆ 360×(3/4) = 270
◆ 360×2 = 720
◆ 36×(3/4) = 27
◆ 36×2 = 72
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◆ ( (10b+a)/2 )×(3/4) = 10a+b
◆ (10b+a)×(3/8) = 10a+b
◆ (30/8)b+(3/8)a = (80/8)a+(8/8)b
◆ (30/8)b-(8/8)b = (80/8)a-(3/8)a
◆ (22/8)b = (77/8)a
◆ 2b = 7a
◆ b/a = 7/2
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◆ 3×9 = 27
◆ 8×9 = 72
◆ (72/8)×3 = 27
◆ (10b+a)×(3/8) = 10a+b
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◆ 3×9 = 27
◆ 8×9 = 72
◆ (27/3)×8 = 72
◆ (10a+b)×(8/3) = 10b+a
◆ (80/3)a+(8/3)b = (30/3)b+(3/3)a
◆ (80/3)a-(3/3)a = (30/3)b-(8/3)b
◆ (77/3)a = (22/3)b
◆ 7a = 2b
◆ 7/2 = b/a
◆ b/a = 7/2
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◆ 4×6 = 24
◆ 7×6 = 42
◆ (24/4)×7 = 42
◆ (10a+b)×(7/4) = 10b+a
◆ (70/4)a+(7/4)b = (40/4)b+(4/4)a
◆ (70/4)a-(4/4)a = (40/4)b-(7/4)b
◆ (66/4)a = (33/4)b
◆ 2a = b
◆ 2 = b/a
◆ b/a = 2
◆ (12/4)×7 = 21
◆ (24/4)×7 = 42
◆ (36/4)×7 = 63
◆ (48/4)×7 = 84
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◆ 2×9 = 18
◆ 9×9 = 81
◆ (18/2)×9 = 81
◆ (10a+b)×(9/2) = 10b+a
◆ (90/2)a+(9/2)b = (20/2)b+(2/2)a
◆ (90/2)a-(2/2)a = (20/2)b-(9/2)b
◆ (88/2)a = (11/2)b
◆ 8a = b
◆ 8 = b/a
◆ b/a = 8
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◆ 13×3 = 39
◆ 31×3 = 93
◆ (39/13)×31 = 93
◆ (10a+b)×(31/13) = 10b+a
◆ (310/13)a+(31/13)b = (130/13)b+(13/13)a
◆ (310/13)a-(13/13)a = (130/13)b-(31/13)b
◆ (297/3)a = (279/3)b
◆ 307a = 99b
◆ 3 = b/a
◆ b/a = 3
◆ (13/13)×31 = 31
◆ (26/13)×31 = 62
◆ (39/13)×31 = 93
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◆ 5×9 = 45
◆ 6×9 = 54
◆ (45/5)×6 = 54
◆ (10a+b)×(6/5) = 10b+a
◆ (60/5)a+(6/5)b = (50/5)b+(5/5)a
◆ (60/5)a-(5/5)a = (50/5)b-(6/5)b
◆ (55/5)a = (44/5)b
◆ 5a = 4b
◆ 5/4 = b/a
◆ b/a = 5/4
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12×2 = 24
21×2 = 42
12×3 = 36
21×3 = 63
12×4 = 48
21×4 = 84
13×2 = 26
31×2 = 62
13×3 = 39
31×3 = 93
14×2 = 28
41×2 = 82
23×2 = 46
32×2 = 64
23×3 = 69
32×3 = 96
24×2 = 48
42×2 = 84
34×2 = 68
43×2 = 86
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2×9 = 18
9×9 = 81
3×9 = 27
8×9 = 72
4×9 = 36
7×9 = 63
5×9 = 45
6×9 = 54
a×9 = ( (a-1)×10 )+( 9-(a-1) )
(11-a)×9 = ( (9-(a-1)×10 )+( 9-(a-1) )
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((10b+a)/2)×(3/4)
10a+b
((9-(a-1)×10)