999/1000x1/100+111/1000x27/100
=999/1000x1/100+111/1000x9x3/100
=999/1000x(1/100+3/100)
=999/1000x1/25
=999/25000
如果本题有什么不明白可以追问,
999/1000x1/100+111/1000x27/100
=999/1000x1/100+111/1000x9x3/100
=999/1000x(1/100+3/100)
=999/1000x1/25
=999/25000
如果本题有什么不明白可以追问,