### Learn to Memorize tables

While starting the learning of tables of double digits we assume that you know tables upto 9, then table of 10 and 11. Let us start with Table of 12. See the table below 12 has two digits - 1 & 2. First we will start with writing tables then we will use our memory to calculate. write 1 to ten for 1 and table of 2 in Preparation column. Now in the Table column write the same figure up to 4 rows 12, 24, 36, 48 till double figure is attained in the table of 2 i.e., 10. Now write the last digit and total of underlined unit.

Table of 12
Preparation Table
1      2 12
2      4 24
3      6 36
4      8 48
5     + 10 60
6     + 12 72
7     + 14 84
8     + 16 96
9     + 18 108
10    + 20 120

Table of 13
Preparation Table
1      3 13
2      6 26
3      9 39
4      + 12 52
5     + 15 65
6     + 18 78
7     + 21 91
8     + 24 104
9     + 27 117
10    + 30 130

Table of 14
Preparation Table
1      4 14
2      8 28
3      + 12 42
4      + 16 56
5     + 20 70
6     + 24 84
7     + 28 98
8     + 32 112
9     + 36 126
10    + 40 140

Table of 15
Preparation Table
1      5 15
2      10 30
3      + 15 45
4      + 20 60
5     + 25 75
6     + 30 90
7     + 35 105
8     + 40 120
9     + 45 135
10    + 50 150

Table of 19
Preparation Table
1      9 19
2      18 38
3      + 27 57
4      + 36 76
5     + 45 95
6     + 54 114
7     + 63 133
8     + 72 152
9     + 81 171
10    + 90 190

Table of 21
Preparation Table
2      1 21
4      2 42
6      3 63
8      4 84
10     5 105
12     6 126
14     7 147
16     8 168
18     9 189
20    + 10 210

Table of 31
Preparation Table
3      1 31
6      2 62
9      3 94
12      4 124
15     5 155
18     6 186
21     7 217
24     8 248
27     9 279
30    + 10 310

Table of 39
Preparation Table
3      9 39
6      18 78
9      + 27 117
12      + 36 156
15     + 45 195
18     + 54 234
21     + 63 273
24     + 72 312
27     + 81 351
30    + 90 390

Table of 79
Preparation Table
7      9 79
14      18 158
21      + 27 237
28      + 36 316
35     + 45 395
42     + 54 474
49     + 63 553
56     + 72 632
63     + 81 711
70    + 90 790

Exercise:

Write the tables of

23 , 28, 29, 35, 37, 41, 46, 53, 89, 91, 95, 99