ARITHMETIC : GEOMETRY
Geometry questions with solution for Railways NTPC, ALP , JE and SSC..
Most expected multiple choice question ❓ and answers with explanation.
3. Find the curved surface area of a hemisphere whose radius is 14 cm.
1. A
Given: ∠BAC = 90° and AD⊥BC.
Since AD⊥BC, the two possible right triangles obtained are ∠ADB and ∠ADC.
Hence, the number of right triangles in the given figure is 3.
I.e., ∠BAC = ∠ADB = ∠ADC = 90°.
2. C
Given two angles are 35° and 95°.
Let the unknown angle be “x”.
We know that sum of angles of a triangle is 180°
Therefore, 35°+95°+x = 180°
130°+ x = 180°
x = 180° – 130°
x = 50°
Hence, the missing angle is 50°.
3. A
Given: Radius = 14 cm.
As we know, the curved surface area of a hemisphere is 2πr² square units.
CSA of hemisphere = 2×(22/7)×14×14
CSA = 2×22×2×14
CSA = 1232
Hence, the curved surface area of a hemisphere is 1232 cm².
4. B
Given: Base area of a cylinder = 154 cm².
As the base area of a cylinder is a circle, we can write πr²= 154cm²
We know that the volume of a cylinder is πr²h cubic units.
V = 154(5) cm³
V = 770 cm³
Hence, the volume of a cylinder is 770 cm².
5. B
Given: Radius = 3 cm
Height = 4 cm
We know that the formula to find the volume of a cone is V = (⅓)πr²h cubic units.
Now, substitute the values in the formula, we get
V = (⅓)π(3)2(4)
V = π(3)(4)
V = 12 π cm³
Hence, the volume of a cone in terms of π is 12 π cm³.


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