Aptitude - Height and Distance - Discussion

P = Perpendicular, H = Hypotenuse, B = Base.

P - B - P
H - H - B
SIN - COS - TAN

Remember this above pattern to know what to use.

For example, in the given question we were given AB (Perpendicular) and angle BPA.
We are asked to find PA (Base).
So we have to find the relation in which both (i.e; perpendicular and base includes).
Since Tan includes Perpendicular and Base both thus we will use it.

Tan30 = Perpendicular/Base,
Tan30 = AB / PA,
Tan30 = 100 / x,
1/root(3) = 100 / x,
x = 100 * root(3),
x = 100 * 1.73,
x = 173m (Ans).

@All.

The correct approach would be using sin 30 as we are given the value of perpendicular i.e. height of the tower and have to find the value of base distance b/w the tower and point p.

@Sankar,

In sin there is perpendicular and hypotenuse.

But we have to find base we cannot use cos also because hypotenuse is not given. Remaining tan which is used.

Hi,

Why here we are not using sin, we will get an answer of 200 if use sin but you are using the formula of tan. Can you give us an explanation?

I think there is a mistake in the answer. Here really we have to use sin as what we need to find out is adjacent side.

Why tan only?

Because we find the height of the tower that we get tan30 because;

tan30 = perpendicular/base.

Here AP needs to be find so using the AB value Tan 30 is taken and Root 3 is 1.73 so the answer will be 173m.

Here AP needs to be find so using the AB value Tan 30 is taken and Root 3 is 1.73 so the answer will be 173m.

Here AP needs to find so using the AB value Tan 30 is taken and root 3 is 1.73. So the answer will be 173m.

Approach 1*1= 1,
1.5*1.5=2.25,
2*2=4,
so.

√ 3 is between 1.5 and 2 so 1.73 is correct.