`a) 2006 xx 125 + 1000`
`=( 2000 + 6) xx 125 + 1000`
`= 2000 xx 125 + 6 xx 125 + 1000`
`= 250 000 + ( 4 + 2) xx 125 + 1000`
`= 250 000 + 4 xx 125 + 125 xx2 + 1000`
`= 250 000 + 500 + 250 + 1000`
`= 250 500 + 250 + 1000`
`= 250 750 + 1000`
`= 251 750`
================================
`b)126 xx 2006-1006`
`= ( 125 + 1) xx 2006 - 1006`
`= 125 xx 2006 + 1 xx 2006 - 1006`
`= 125 xx 2006 + 2006 - 1006`
`= 125 xx ( 2000 + 6) + ( 2006 - 1006)`
`= 125 xx 2000 + 125 xx 6 +1000`
`= 250 000 + 125 xx ( 4 + 2) + 1000`
`= 250 000 + 125 xx 4 + 125 xx 2 +1000`
`= 250 000 + 500 + 250 + 1000`
`= 250 500 + 250 + 1000`
`= 250 750 + 1000`
`=251 750`
