`B = ( 67/111 + 2/33 - 15/117 ) xx ( 1/3 - 1/4 - 1/2 ) xx 2018`
`B = 2836/5291 xx ( 4/12 - 3/12 - 6/12 ) x 2018`
`B = 2836/5291 xx ( - 5 )/12 xx 2018`
`B = ( - 3545 )/15873 xx 2018`
`B = ( - 7513810 )/15873`
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`C = ( 1 + 2 + 3 + .... + 8 + 9 )/( 11 + 12 + 13 + .... + 24 + 25 )`
`C = ( ( 9 + 1 ) . 9 : 2 )/( ( 25 + 11 ) . 15 : 2 )`
`C = ( 10 . 9 : 2 )/( 36 . 15 : 2 )`
`C = ( 90 : 2 )/( 540 : 2 )`
`C = 45/270 = 1/6`
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`G = 19991999 xx 1998 - 19981998 xx 1999`
`G = 1999 xx 10 001 xx 1998 - 1998 xx 10 0001 xx 1999`
`G = 0 (` Do cả `2` vế giống nhau nên hiệu là `0 )`
