Two giant identical poles have been planted in the ground.

Question

1. Two giant identical poles have been planted in the ground. One of the
poles was planted deeper than the other pole. The shadow of pole A is 10
meters long and the shadow of pole B is 8 meters long. How tall is pole
B?
(1) Pole A is hoisted 14 meters in the air.
(2) Pole B is located 2 meters from pole A

amit2k9 · Answer

Good one.

a using similar triangle principle,

pole B is behind pole A as both poles are identical meaning same heights.

thus 14/Hoisted height of pole B = 10/ (10 +2)

= 16.8 approx.

b. hoisted heights of poles not given.Hence redundant information.

A it is.

arjunbt · Answer

Good question, 
I learn from the question that one of the pole is dipped inside the ground and other one is just planted. 
from this we can say that the length of 1st pole is 14 and the second pole's length above the ground will be 14 * 8 / 10 according to rule of similar triangle which comes out to be around 12. 
Hoisted length of the second pole is 12. and hence answer is "A"

mohan514 · Answer

can anyone make the theory more clear,,
i am not familiar with the principleof similar triangles whatever you mentioned,,
please explain thanks in advance,,

viks4gmat · Answer

guys can someone explain what this means "One of the poles was planted dipper than the other pole."

@mohan: in this question you really dont need to know mathematical stuff

All you need to know is the common sense that the larger the pole, the longer its shadow..
so for if 14 mt long pole casts a shadow of 10 mts, 
x will cast a shadow of 8 mts

therefore x = 14 *8 /10

mohan514 · Answer

i actually di it that way but just wanted to know if there is some maths which i was missing
and whatever you have asked for,,
both the poles are of similar height but one pole is planted deeper means its height above the ground is decreased as it is burried deep in the ground when compared to the other pole which has the same height

manishgeorge · Answer

but guys, the question is asking us to find the length of the pole not the length above the ground

viks4gmat · Answer

thanks... the question says dipper and i went on to think one pole has a dipper-light of some sort that was casting a shadow etc... so do u mind correcting this in the problem... it helps people like me not get confused :-D

and if you have another core heights and distances question.. maybe then we can help you with your similar trianges approach

and if you have another core heights and distances question.. maybe then we can help you with your similar trianges approach

144144 · Answer

E for me - no matter how long is the shadow - we get no information about how much is in the ground. Are you sure OA is A???

prateekbhatt · Answer

dont think it can be A...because pole b is 2 m short...

IMOE

shashankp27 · Answer

Should be E . 
Moreover , the question does not clearly say that "on which side of Pole A is Pole B". No doubt that the shadows will be in the same direction , however won't the dimensions of the figure change if B lies to left of A as opposed to right ?

mohan514 · Answer

picked up this question from some unknown sourse ..there are mistakes in the material

not sure about the answer though given in the material

bumpbot · Answer

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Two giant identical poles have been planted in the ground.

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