用简便方法计算!2/7x5/9x(36x28) 7/9÷13/5+2/9x5/13(5/6-7/12x15/14)÷5/4 26/21-1/5-8/9÷10/9

来源:学生作业帮助网 编辑:作业帮 时间:2018/04/27 06:48:57
用简便方法计算!2/7x5/9x(36x28)7/9÷13/5+2/9x5/13(5/6-7/12x15/14)÷5/426/21-1/5-8/9÷10/9用简便方法计算!2/7x5/9x(36x28

用简便方法计算!2/7x5/9x(36x28) 7/9÷13/5+2/9x5/13(5/6-7/12x15/14)÷5/4 26/21-1/5-8/9÷10/9
用简便方法计算!
2/7x5/9x(36x28) 7/9÷13/5+2/9x5/13
(5/6-7/12x15/14)÷5/4 26/21-1/5-8/9÷10/9

用简便方法计算!2/7x5/9x(36x28) 7/9÷13/5+2/9x5/13(5/6-7/12x15/14)÷5/4 26/21-1/5-8/9÷10/9
1)原式=(2*5*36*28)/(7*9)=2*5*4*4=10*16=160
2)原式=(7/9)*(5/13)+(2/9)*(5/13)
=(5/13)*(7/9++2/9)
=5/13
3)原式=(5/6-5/8)*4/5
=4/6-1/2=4/6-3/6=1/6
4)原式=26/21-1/5-4/5
=26/21-1=26/21-21/21=5/21