The HCF and LCM of 2 numbers are Xand Y are respectively 3 and 105. if x+y= 36 then 1/x+1/y=?

Dear student
HCF of two numbers x and y=3LCM of two numbers x and y=105and x+y=36   ...(1)We know,HCF×LCM=Product of two numbers3×105=xyxy=315x=315y     ....(2)Put the value of x in (1), we get315y+y=36315+y2-36y=0y2-36y+315=0y2-15y-21y+315=0yy-15-21(y-15)=0(y-21)(y-15)=0y-21=0 or y-15=0y=21 or y=15Case 1: When y=21 then x=31521=15Then, 1x+1y=115+121=21+15315=36315=435Case 2: When y=15  then x=31515=21Then, 1x+1y=121+115=15+21315=36315=435 
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