Question
From a point on the ground, the angle of elevation of
the top of a tower is 45°. On walking 20 m towards the tower, the angle of elevation becomes 60°. Find the height of the tower.Solution
Let initial distance from tower = x m, height = h m. tan 45° = h / x ⇒ 1 = h/x ⇒ h = x After moving 20 m towards tower, distance = x − 20: tan 60° = h / (x − 20) ⇒ √3 = h/(x − 20) Since h = x: √3 = x / (x − 20) √3(x − 20) = x √3 x − 20√3 = x (√3 − 1)x = 20√3 x = 20√3 / (√3 − 1) Rationalize: x = 20√3(√3 + 1) / (3 − 1) = 10√3(√3 + 1) = 10(3 + √3) Height h = x = 10(3 + √3) m.
In the question, assuming the given statements to be true, find which of the conclusion (s) among given two conclusions is/are definitely true and then...
In the question, assuming the given statements to be true, find which of the conclusion (s) among given three conclusions is /are definitely true and ...
Statements: D % E, E & A, A @ B, B # C
Conclusions: I. C & AÂ Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â II. D # B
...Statements:
A ≤ Z < X < I; L > P > C > B = I;
Conclusions:
I) Z > L
II) B > A
Statement: P = Q ≥ S ≥ T < O < Z ≥ X; T > H
Conclusion:
I.  H ≥ X
II. Â P > H
...Statements: S = R, T ≤ U, O < J, T ≤ J, U > R
Conclusion:
I. R ≥ T
II. R < T
In the following question the relationship between different elements is given in the statements followed by two conclusions I and II. Read the statem...
Statements:Q = S > T > Z; T > Y = H < I
Conclusions: I. Z > H II. I > Z
Statement: L ≥ X ≤ Z > Y ≤ A, Y = B ≥ CÂ
Conclusion: I. C >A                         II. A ≥ C
...Statements: P < R > U = T ≥ V = Q; Q < W = X > S = D
Conclusions:
I. X > V
II. S > V
III. X > T
