Depreciation

1. Sum of digits of 6 years will be 21. (1+2+.....6 = 21)

2. Multiplying Factor (N) for each year will be original cost - final cost  divided by digital sum

i.e. N = (126000 - 0) / 21.

or N = 6000.

So, depreciation for each year will be as ...

First year .........   6 * N  = 36000.

Second year ..... 5 * N

Third year ....      4 * N

Forth year ....     3 * N  = 18000.

Fifth Year  .....    2 * N

Sixth Year .....   1 * N  = 6000