Railways
R.R.C. (Hazipur) Solved Paper Held on 27-10-2013
question_answer
A person starts from a point A and travels 3 km eastwards to B and then turns left and travels thrice that distance to reach C. He again turns left and travels five times the distance he covered between A and B and reaches his destination D. The shortest distance between the starting point and the destination is?
A)12 km
B)15 km
C)16 km
D)18 km
Correct Answer:
B
Solution :
As wee know \[{{(ac)}^{2}}={{(ab)}^{2}}+{{(bc)}^{2}}\] \[{{(ac)}^{2}}={{(12)}^{2}}+{{(9)}^{2}}\] \[{{(ac)}^{2}}=144+81\] \[{{(ac)}^{2}}=225\] \[ac=\sqrt{225}=15\,\,km\]