There are a few tricks to multiply a double digit number by 9, according to different conditions:

- The number is a multiple of 11.
- The tens digit is less than the ones digit by one.
- The tens digit is less than the ones digit.
- The tens digit is greater than the ones digit.

In this page, we are going to discuss about case four, where the number a tens digit is greater than the ones digit. (Example, 42, 85, 62, 93 ....)

### Condition:

- The multiplicand is a double digit number where the tens digit is greater than the ones digit .
- The multiplier is 9.

__Example 1__
41 x 9 = ?

- Deduct the multiplicand by 10, and then multiply the answer by 10. In this case, 41 - 10 = 31. 31 x 10 = 310.

- Find the 100's complement of the multiplicand. In this case, 100 - 41 = 59. Sum up the answer obtained in step 1 and 2.

**Example 2**

96 x 9 = ?

- (96 - 10) x 100 = 860
- 100 - 96 = 4

__Example 3__
62 x 9 = ?

- (62 - 10) x 100 = 520
- 100 - 62 = 38

Therefore, 62 x 9 = 520 + 38 = 558

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