分数的简便计算:1/11+14/15+17/21+34/35+37/56+87/88=
1/11+14/15+17/21+34/35+37/56+87/88!神啊!给我答案啊!
1/11+14/15+17/21+34/35+37/56+87/88
=1/11+1-1/88+1-1/15+1-4/21+1-1/35+1-19/56
=5+7/88-1/5(1/3+1/7)-4/21-19/56
=5+7/88-1/5*10/21-4/21-19/56
=5+7/88-2/7-19/56
=5+7/88-5/8
=5-6/11
=49/11
简便计算:60%×99+35/56×17+5/6÷1/19
60%×99+35/56×17+5/6÷1/19
=0.6×99+85/8+95/6
=0.6×(100-1)+11-3/8+16-1/6
=60+11+16-(0.6+3/8+1/6)
=86-(72+45+20)/120
=86-135/120
=84又21/24
简便计算:1998*(1/11-1/2009)+11*(1/1998-2009)-2009*(1/11+1/1998)+3
1998*(1/11-1/2009)+11*(1/1998-1/2009)-2009*(1/11+1/1998)+3
=1998/11-1998/2009+11/1998-11/2009-2009/11-2009/1998+3
=(1998-2009)/11-(1998+11)/2009+(11-2009)/1998+3
=-11/11-2009/2009-1998/1998+3
=-3+3
=0
简便计算,442/34 15*21
简便计算,442/34 15*21
442/34 15*21
=13+315
=328
直接计算
56/213-14/56+56的简便计算
56/213-14/56+56的简便计
56/213-14/56+56
=56*(213-14+1)
=56*200
=11200
3/1 + 15/1 + 35/1 + 63/1 +99/1的简便计算
应该是1/3+1/15+1/35+1/63+1/99吧
用裂项法,答案是二分之一倍的(1-三分之一+三分之一-五分之一+五分之一-七分之一+七分之一-九分之一+九分之一-十一分之一)为十一分之五~
16/35×21/40简便计算
16/35×21/40简便计算
16/35×21/40
=16/40×21/35
=2/5×3/5
=6/25
简便计算: 1/14+1/24+1/36+1/48+1/60+1/72
1/12+1/24+1/36+1/48+1/60+1/72
=(1-3-1/4)+(1/4-1/6)*1/2+1/36+(1/6-1/8)*1/2+1/60+(1/8-1/9)
=(1/3-1/4+1/8-1/9)+【(1/4-1/6+1/6-1/8)*1/2】+1/36+1/60
=7/72+1/16+1/36+1/60
=(7/72+1/36)+1/16+1/60
=1/8+1/16+1/60
=3/16+1/60
=49/240
11/14x4/17+13/14x11/17的简便计算
11/14×4/17+13/14×11/17
=4/14×11/17+13/14×11/17
=(4/14+13/14)×11/17
=17/14×11/17
=11/14