1997/1998*998
=(1998-1)*998/1998
=998-998/1998
=997+1000/1998
=887+500/999
51又三分之2÷3分之5+71又4分之3÷4分之7
=(50+5/3)÷(5/3)+(70+7/4)÷(7/4)
=50÷5/3+5/3÷5/3+70÷7/4+7/4÷7/4
=30+1+40+1
=72
√希望你能看懂,你能明白,赞同