1-9/14+8/21+1/7-17/35-27/7
=420/420-270/420+160/420+60/420-204/420-1620/420
=(420-270+160+60-204-1620)/420
=-1454/420
=-727/210
1-9/14+8/21+1/7-17/35-27/7
=420/420-270/420+160/420+60/420-204/420-1620/420
=(420-270+160+60-204-1620)/420
=-1454/420
=-727/210