Aptitude - Height and Distance - Discussion

Discussion Forum : Height and Distance - General Questions (Q.No. 3)
3.
The angle of elevation of a ladder leaning against a wall is 60° and the foot of the ladder is 4.6 m away from the wall. The length of the ladder is:
2.3 m
4.6 m
7.8 m
9.2 m
Answer: Option
Explanation:

Let AB be the wall and BC be the ladder.

Then, ACB = 60° and AC = 4.6 m.

AC = cos 60° = 1
BC 2

BC = 2 x AC
= (2 x 4.6) m
= 9.2 m.

Discussion:
45 comments Page 4 of 5.

GAGAN said:   4 years ago
@Anil Kumar.

But they have asked BC not AB. Why are you finding AB?
(1)

Altamash Bagwan said:   6 years ago
In this question, cos indicate is an adjacent side/hypotenuse side.

JIT said:   8 years ago
If we take,

tan30=AC/BC,
BC=7.8.

Why can't we solve in this way?
(1)

Anant said:   1 decade ago
tan60 = x/4.6.

x = tan60*4.6.
x = 1.732*4.6.

Therefore, x = 7.8.

Brinda said:   6 years ago
@Chiru.

Yes, you are right and when Tan is taken answer is 7.9.

Fgrg said:   1 decade ago
Can't we do this with the 30, 60, 90 triangle method?

Deepali said:   4 years ago
why we take cos here? Explain please.
(1)

Rajan said:   9 years ago
Why can't we use sec instead of cos?
(1)

Neeraj said:   7 years ago
Why can't we solve this using tan?

Praveen kumar said:   9 years ago
Great answer Thanks @Rahul Rami.
(1)


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