1⼀2-(6⼀7-5⼀8)-1⼀7,等于几分之几? 2⼀21+(2⼀3-2⼀7)+6⼀7等于?

2025-01-12 15:22:22
推荐回答(2个)
回答1:

1/2-(6/7-5/8)-1/7
=1/2-6/7+5/8-1/7
=(1/2+5/8)-(6/7+1/7)
=9/8-1
=1/8

2/21+(2/3-2/7)+6/7
=2/21+2/3-2/7+6/7
=(2/21+2/3)+(6/7-2/7)
=17/21+4/7
=29/21

回答2:

1/2-(6/7-5/8)-1/7 =1/2-6/7+5/8-1/7 =(1/2+5/8)-(6/7+1/7) =9/8-1 =1/8 2/21+(2/3-2/7)+6/7 =2/21+2/3-2/7+6/7 =(2/21+2/3)+(6/7-2/7) =17/21+4/7 =29/21