Here is a very nifty way for writing multiplication table of numbers ending in 9.

Let’s say you want to write multiplication table of 29.

Notice that the ten’s digit is 2. The next higher number to 2 is 3.

So, the first part of each row will be previous row’s ten’s digit plus 3. And the last part of each row will be complement of that multiplier i.e. the unit Place digit will be 9, 8, 7, 6, 5, 4, 3, 2, 1 & 0.

29 × 3 = (5+3) / 7 = 87

29 × 4 = (8+3) / 6 = 116

29 × 4 = (8+3) / 6 = 116

29 × 5 = (11+3)/ 5 = 145

29 × 6 = (14+3)/ 4 = 174

29 × 7 = (17+3)/ 3 = 203

29 × 8 = (20+3)/ 2 = 232

29 × 9 = (23+3)/ 1 = 261

29 × 10 = (26+3)/ 0 = 290

See the pattern? We can write any table, with digit 9 at unit place, by using this trick.

Another Example: Table of 59 (say)

The ten’s digit here is 5. The next higher number to 5 is 6.

So, the first part of each row will be 6 plus previous answer’s ten’s digit. The last part of each row will be 9, 8, 7, 6, 5, 4, 3, 2, 1 & 0.

59 × 1 = 5 / 9 = 59

59 × 2 = (5+6) / 8 = 118

59 × 3 = (11+6) / 7 = 177

59 × 4 = (17+6) / 6 = 236

59 × 5 = (23+6)/ 5 = 295

59 × 6 = (29+6)/ 4 = 354

59 × 7 = (35+6)/ 3 = 413

59 × 8 = (41+6)/ 2 = 472

59 × 9 = (47+6)/ 1 = 531

59 × 10 = (53+6)/ 0 = 590

We can't use it for 19?

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