巧算(1+1⼀2)X(1-1⼀2)X(1+1⼀3)X(1-1⼀3)X(1+1⼀4)X(1-1⼀4);1又1⼀4X64+12.5X3又1⼀2+1除以4⼀5

2024-12-01 02:53:32
推荐回答(2个)
回答1:

(1+1/2)X(1-1/2)X(1+1/3)X(1-1/3)X(1+1/4)X(1-1/4);
=3/2*1/2*4/3*2/3*5/4*3/4
=5/8

1又1/4X64+12.5X3又1/2+1除以4/5
=1.25×64+12.5×3.5+1×5/4
=1.25×(64+35+1)
=1.25×100
=125

回答2:

(1+1/2)X(1-1/2)X(1+1/3)X(1-1/3)X(1+1/4)X(1-1/4)
=[(1+1/2)X(1-1/2)[X[(1+1/3)X(1-1/3)]X[(1+1/4)X(1-1/4)]
=(1-1/4)(1-1/9)(1-1/16)
=(3/4)(8/9)(15/16)
=5/8

1又1/4X64+12.5X3又1/2+1除以4/5
=(5/4)*64+(25/2)*(7/2)+1*(5/4)
=80+(175/4+5/4)
=80+45
=125