设甲单独做需X天,则乙单独做需(1又(1/2))*X=(3*X/2)天.
((1/X)+(1/(3*X/2)))*2+(1/(3*X/2))=1
2/X+2/(3*X/2)+1/(3*X/2)=1
2/X+3/(3*X/2)=1
2/X+2/X=1
X=4天
3*X/2=6天
甲单独做需4天,则乙单独做需6天.
设甲单独做需X天,则乙单独做需(1又(1/2))*X=(3*X/2)天.
((1/X)+(1/(3*X/2)))*2+(1/(3*X/2))=1
2/X+2/(3*X/2)+1/(3*X/2)=1
2/X+3/(3*X/2)=1
2/X+2/X=1
X=4天
3*X/2=6天
甲单独做需4天,则乙单独做需6天.