<PRE><B>Question 1027961</B>
A  	x		days						
B  	x+	10	days						
A  	1/x of the job in	hour  							
B  	1/(x+	10	)of the job in 1			day			
Together they take 1/x+ 1/(x+		10	)of the job in 1			day			
Together they do the job in		12	days	12	days				
Together they do  1/		12	of the job in 1			day			
1/x	+	1/(x+	10	)=	1/	12			
LCD =x(x+	10	)   							
(x+	10	)+x=	1/	12	(x	+	10	)x	
(  	2	x+	10	) *	12	=	x^2+	10	x
24	x+	120	=	x^2+	10	x			
x^2	-14	x	-120	=	0				
Find the roots of the equation 

x^2-20x+6x-120=0

x(x-20)+6(x-20)=0

(x-20)(x+6)=0

x= 20 OR -6

Ignore negative

x= 20

A takes 10 days
B takes 20 days   to do the job alone
									
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