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MathsHardNumerical2020 · 06 Sep Shift 1

Q71.The angle of elevation of the top of a hill from a point on the horizontal plane passing through the foot of the hill is found to be 45°. After walking a distance of 80 meters towards the top, up a slope inclined at angle of 30° to the horizontal plane the angle of elevation of the top of the hill becomes 75°. Then the height of the hill (in meters) is _____.

What This Question Tests

This problem involves using trigonometry and geometric principles to solve a complex height and distance scenario, requiring careful drawing and application of sine/cosine rules.

Concepts Tested

Trigonometric ratiosAngle of elevationGeometry of triangles

Formulas Used

tan θ = opposite/adjacent

Sine Rule

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📋 Question Details

Chapter
Trigonometric Functions & Equations
Topic
Heights and Distances
Year
2020
Shift
06 Sep Shift 1
Q Number
Q71
Type
Numerical
NCERT Ref
Class 10 Mathematics Ch 9: Some Applications of Trigonometry

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