①1-【-1-(-3/7)-5-(-4/7)】+|-6|
=1-(-1+3/7-5+4/7)+6
=1—(-5)+6
=1+5+6
=12
②12又¼+(-0.75)-(4又½)-(+3.25)+(+7¾)
=(12又¼+7¾) +(-0.75)-(4又½)-(+3.25)
=20-0.75-3.25-4又½
=16-4又½
=11又½
①1-【-1-(-3/7)-5-(-4/7)】+|-6|
=1-(-1+3/7-5+4/7)+6
=1—(-5)+6
=1+5+6
=12
②12又¼+(-0.75)-(4又½)-(+3.25)+(+7¾)
=(12又¼+7¾) +(-0.75)-(4又½)-(+3.25)
=20-0.75-3.25-4又½
=16-4又½
=11又½