第1个回答 2009-11-16
1. 27×26分之25
=(26+1)*25/26
=26*25/26+25/26
=25+25/26=25又26分之25
2. 3.5×1又4分之1+1又2分之1÷5分之4
=3.5*5/4+3/2*5/4
=5/4*(3.5+1.5)
=25/4
3. (7分之65-9分之65)÷(7分之5-9分之5)
=65*(7分之1-9分之1)÷<5*(7分之1-9分之1)>
=65÷5
=13
4. 2.5×0.25×1600
=2.5*0.25*(4*400)
=2.5*4*(0.25*400)
=10*100
=1000
5. 4.8×25=1.2*(4*25)=1.2*100=120
解方程:
1. 5又5分之1-2×(X-4)=5
解:26/5-2x+8=5
2x=41/5
x=4.1
2. 3×(X+90%)=5×(X-1又10分之7)
解:3X+2.7=5X-8.5
2X=11.2
X=5.6
注:*为乘号 /为分数线