Herman Yeung - 印度吠陀數學的 further explanation

1142 x 324
= (1000 + 100 + 40 + 2) x (300 + 20 + 4)
= 1000 x 300
    + 1000 x 20 + 100 x 300
    + 1000 x 4 + 100 x 20 + 40 x 300
    + 100 x 4 + 40 x 20 + 300 x 2
    + 40 x 4 + 2 x 20
    + 2 x 4
= (1 x 3) x 100,000
    + (1 x 2 + 1 x 3) x 10,000
    + (1 x 4 + 1 x 2 + 4 x 3) x 1,000
    + (1 x 4 + 4 x 2 + 3 x 2) x 100
    + (4 x 4 + 2 x 2) x 10
    + (2 x 4) x 1
=     3 x 100,000
    + 5 x 10,000
    + 18 x 1,000
    + 18 x 100
    + 20 x 10
    + 8 x 1
= 370,008