`A = 1.3 + 3.5 + 5.7 + ... + 97.99 + 99.101`

`6A = 1.3.6 + 3.5.6 + 5.7.6 + ... + 97 . 99 . 6 + 99 . 101 . 6`

`6A = 1.3.[5 - (-1)] + 3 . 5 . (7 - 1) + 5.7.(9-3) + ... + 97 . 99 . (101 - 95) + 99.101.(103-97)`

`6A = 1 . 3 . 5 - (-1) . 1 . 3 + 3 . 5 . 7 - 1 . 3 . 5 + 5.7.9 - 3 . 5 . 7 + ... + 97 . 99 . 101 - 95 . 97 . 101 + 99 . 101 . 103 - 97 . 99 . 101`

`6A = 1 . 1 . 3 + (1 . 3 . 5 - 1 . 3 . 5) + (3 . 5 . 7 - 3 . 5 . 7) + (5 . 7 . 9 - 5 . 7 . 9) + ... + (97 . 99 . 101 - 97 . 99 . 101) + 99 . 101 . 103`

`6A = 3 + 99 . 101 . 103`

`6A = 1029900`

`A = 171650`