The angle of elevation of a 5 m long ladder leaning against a wall is 45 degrees and the foot of the ladder is 3 m away from the…

Quantitative Aptitude ·Previously asked in JKSSB Sub Inspector (Executive) 2017

View the full solved paper: JKSSB Sub Inspector (Executive) 2017

Question

The angle of elevation of a 5 m long ladder leaning against a wall is 45 degrees and the foot of the ladder is 3 m away from the wall. The height of the wall up to the point where the ladder is resting against it is:

  1. A. 2 m
  2. B. 3 m
  3. C. 4 m (Correct answer)
  4. D. Cannot be determined on the basis of the given information

Correct Answer

Option C — 4 m

Detailed Solution & Explanation

The correct answer is 4 m.

Key Points

  • The ladder is 5 m long, foot is 3 m from the wall, angle of elevation = 45°.
  • Using Pythagoras: height² = 5² − 3² = 25 − 9 = 16 → height = 4 m. Note: the problem states angle = 45° but the geometry (3-4-5 right triangle) gives angle = arctan(4/3) ≈ 53°.
  • The answer from Pythagorean theorem is 4 m.

Topics covered: JKPSI JKSSB 2017 Quantitative Aptitude Geometry Trigonometry