If the shortest distance between the lines x-λ / 2 = y-4 / 4 = z-7 / 8 , x-2 / 1 = y-3 / 2 = z-4 / 4 is 13/√ 21

Question

If the shortest distance between the lines \(\frac {x-\lambda}{2} = \frac {y-4}{4} = \frac {z-7}{8}, \frac {x-2}{1} = \frac {y-3}{2} = \frac {z-4}{4} \) is \(\frac {13}{\sqrt {21}}\) then sum of values of λ is

(1) 23/4 

(2) 23/5 

(3) 21/4 

(4) 25/2

Answer 1

Correct option is (2) 23/5