Question
The angles of elevation of the top of a flagpole from
two points A and B on level ground are 30° and 60° respectively. The points A and B are on the same straight line as they are 20 meters apart. Find the height of the flagpole.Solution
Let the height of the flagpole be h meters, and let the distance of point A from the base of the pole be x meters. tan 30° = h/x. 1/√3 = h/x. h = x/√3. From the triangle formed with the 60° angle, tan 60° = h/(x - 20). √3 = h/(x - 20). h = √3(x - 20). Equating the two expressions for h: x/√3 = √3(x - 20). Multiply through by √3: x = 3(x - 20). x = 3x - 60. 2x = 60. x = 30 meters. Substitute x into h = x/√3: h = 30/√3 = 10√3 meters. Correct answer: a) 10√3 meters
How many persons are sitting between Q and R, when counted clockwise of Q?
A is related to F in the same way as N is related to Q. Which of the following is P related to following the same pattern?
Who among the following person sits at the longer side of the table?
I) The one who sits immediate left of W
II) V
III) The ...
Who among the following sits second to the left of E?
Which of the following statements is definitely false?
Who among the following stands third to the right of T?
Five products, K, L, M, N and O, are placed in a row facing towards the east (not necessarily in the same order). M is second to the left of U. K is sec...
Who among the following lives on floor no.3?
Seven persons—T, U, V, W, X, Y and Z are sitting along a circle facing the centre. T is between Z and W. V is second to the right of W and is between...
Five persons are standing in a row facing north. B is standing at the second place to the right of S. Y is not next to L. If Q is standing second from t...
