67/69x31简算
简算练习!!! -
67/69x31 =(1-2/69)x31 =1x31-2/69x31 =31-62/69 =30又7/69 139x137/138+137x1/138 =139x137/138+137/138 =(139+1)x137/138 =140x(1-1/138)=140-140/138 =140-70/69 =138又68/69 5/17x9/24+4/17x7/24 =(5x9+4x7)/(17x24)=73/408 如果本题有什么不明白可以追有帮助请点赞。
(67/69)x31 =[(69-2)/69]x31 =[1-(2/69)x31 =31-62/69 =30+69/69-2/69 =30又69分之67 2 (2003/2002)x1999 =[(2002+1)/2002]x1999 =[1+(1/2002)]x1999 =1999+1999/2002 =1999又2002分之1999 3 原式=(125+1+1/49)÷25 =（125+50/49)÷25 =125÷25+(50/49)说完了。
67/69x31 =(1-2/69)x31 =1x31-2/69x31 =31-62/69 =30又7/69 139x137/138+137x1/138 =139x137/138+137/138 =(139+1)x137/138 =140x(1-1/138)=140-140/138 =140-70/69 =138又68/69 5/17x9/24+4/17x7/24 =(5x9+4x7)/(17x24)=73/408 如果本题有什么不明白可以追有帮助请点赞。
(67/69)x31 =[(69-2)/69]x31 =[1-(2/69)x31 =31-62/69 =30+69/69-2/69 =30又69分之67 2 (2003/2002)x1999 =[(2002+1)/2002]x1999 =[1+(1/2002)]x1999 =1999+1999/2002 =1999又2002分之1999 3 原式=(125+1+1/49)÷25 =（125+50/49)÷25 =125÷25+(50/49)说完了。
