basic number facts in four operation裡面的basic number facts 應該怎麼翻譯?

basic number facts 應該怎麼翻譯?

數字　的基本事實．

例如說：
要是一個數字（像是１２３）可以被３整除，任意對調它的字母的數字（像是３１２或是２１３）還是可以被３整除．

The following is also one of the many “basic number facts(數字運算定律)” in math operation introduced by the book named "德氏心算"
1. 64 X 33 ?= 2,112
64 = (6+4)=10=(1+0)= 1
33=(3+3)=6
1x6=6(the answer must equal to “6” )
2112=(2+1+1+2)=6
So, 2112 is very possibly a correct answer.

2. 7,653 X 4,589 ?= 35,119,617
7653 = (7+6+5+3)=21=(2+1)=3
4589 = (4+5+8+9)=26=(2+6)=8
3x8=24=(2+4)=6(the answer must be equal to “6” )
35,119,617=(3+5+1+1+9+6+1+7)=33=(3+3)=6
So, 35,119,617 is very possibly a correct answer.

3. 3,692x 345 ?= 1,273,740
3,692= (3+6+9+2)=20=(2+0)=2
345= (3+4+5)= 12= (1+2)=3
2x3=6 (the answer must be equal to “6”)
1,273,740= (1+2+7+3+7+4+0)=24=(2+4)=6
So, 1,237,740 is very possibly a correct answer.

4.238,765x654,321?=156,228,953,565
238,765=(2+3+8+7+6+5)=22=(2+2)=4
654,321=(6+5+4+3+2+1)=21=(2+1)=3
4X3=12=(1+2)= 3(the answer must be equal to “3”) 156,228,953,565?=(1+5+6+2+2+8+9+5+3+5+6+5)=57=(5+7)=12=(1+2)=3
So, 156,228,953,565 is very possibly a correct answer.

5. 563,345x446,699 ?= 251,644,648,155
563,345=(5+6+3+3+4+5)=26=(2+6)=8
446,699=(4+4+6+6+9+9)=38=(3+8)=11=(1+1)=2
8x2=16=(1+6)=7(the answer must be equal to “7”)
251,644,648,155=(2+5+1+6+4+4+6+4+8+1+5+5)=51=(5+2)=6
So, 251,644,648,155 is definitely a wrong answer.

PS:好像有人有興趣那再學小半章好了 - 1060426
帶5尾數平方
5 x 5 = 25
15 x 15 = 1 X ( 1 + 1 )… 25 = 225
25 x 25 = 2 X ( 2 + 1 )… 25 = 625
35 x 35 = 3 X ( 3 + 1 )… 25 = 1225
45 x 45 = 4 X ( 4 + 1 )… 25 = 2025
55 x 55 = 5 X ( 5 + 1 )… 25 = 3025
65 x 65 = 6 X ( 6 + 1 )… 25 = 4225
75 x 75 = 7 X ( 7 + 1 )… 25 = 5625
85 x 85 = 8 X ( 8 + 1 )… 25 = 7225
95 x 95 = 9 X ( 9 + 1 )… 25 = 9025
105 x 105 = 10 X ( 10 + 1 )… 25 =11025
115 x 115 = 11 X ( 11 + 1 )… 25 =13225
11 X 12 = 1(1 X 1)3(1+2)2(1 X 2)  132
125 X125 = 12 X ( 12 + 1 ) … 25 = 15625
12 X 13 = 1(1 x 1)5(2+3)6(2 x3)  156
…
頭數相加為偶數且帶5尾數之相乘
25 x 45 = (2 x 4 ) + (2 + 4 )/2 … 25 = 1125
35 x 55 = (3 x 5 ) + (3 + 5 )/2 … 25 = 1925
55 x 75 = (5 x 7 ) + (5 + 7 )/2 … 25 = 4125
75 x 95 = (7 x 9 ) + (7 + 9 )/2 … 25 = 7125
15 x 55 = (1 x 5 ) + (1 + 5 )/2 … 25 = 825
35 x 75 = (3 x 7 ) + (3 + 7 )/2 … 25 = 2625
15 x 35 = (1 x 3 ) + (1 + 3 )/2 … 25 = 525
85 x 25 = (8 x 2 ) + (8 + 2 )/2 … 25 = 2125
45 x 65 = (4 x 6 ) + (4 + 6 )/2 … 25 = 2925
65 x 85 = (6 x 8 ) + (6 + 8 )/2 … 25 = 5525
95 x 55 = (9 x 5 ) + (9 + 5 )/2 … 25 = 5225
…
頭數相加為奇數且帶5尾數之相乘
25 x 35 = (2 x 3 ) + (2 + 3 )/2去小數 … 75 = 875
35 x 45 = (3 x 4 ) + (3 + 4 )/2去小數 … 75 = 1575
55 x 85 = (5 x 8 ) + (5 + 8 )/2去小數 … 75 = 4675
75 x 85 = (7 x 8 ) + (7 + 8 )/2去小數 … 75 = 6375
15 x 45 = (1 x 4 ) + (1 + 4 )/2 去小數…. 75 = 675
35 x 65 = (3 x 6 ) + (3 + 6 )/2去小數 … 75 = 2275
15 x 65 = (1 x 6 ) + (1 + 6 )/2去小數 … 75 = 975
85 x 15 = (8 x 1 ) + (8 + 1 )/2去小數 … 75 = 1275
45 x 75 = (4 x 7 ) + (4 + 7 )/2去小數 … 75 = 3375
65 x 95 = (6 x 9 ) + (6 + 9 )/2去小數 … 75 = 6175
95 x 45 = (9 x 4 ) + (9 + 4 )/2去小數 … 75 = 4275
…
原理為何? 要自己想!
資料來源：絕版書”德氏心算”之兩個小半章(整本書大概七、八章)
欲學全套，去大圖書館找找看

數字的基本運算法則