Question

The height of a triangular prism is 10 cms. The sides of the base are 3 cm, 4 cm, 5 cm. Find its
i) Lateral surface area (L.S.A).
ii) Total surface area
(iii)Volume.
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Answer 1

Answer:

Given:

Height of triangular prism = 10 cm

Sides of base = 3, 4, 5 cm

To find:

Total surface area of prism = ?

Solution:

First of all, let us have a look at the formula for Total Surface Area of triangular prism:

Where B is the area of base

p is the perimeter of base and

h is the height of prism.

here base is a right angled triangle (because 3, 4, 5 is a triplet) Base and Height will be 3 , 4 cm or 4, 3 cm and 5 will be hypotenuse.

So formula for B:

So, TSA = 6 + (3+4+5)  10 = 6 + 120 = 126  

So, total surface area of given prism is 126.

Answer 2

Answer:

The lateral surface area, total surface area, and volume of the prism are 120cm², 180cm² and 1200cm³ respectively.

Step-by-step explanation:

Given:

Side 1 (S₁): 3cm

Side 2 (S₂): 4cm

Side 3 (S₃): 5cm

Height (H): 10cm

1) Lateral surface area = (S₁+S₂+S₃)H = (3+4+5)10 =120cm²

2) Total surface area =  LSA + S₁*S₂*S₃= 120+60 = 180cm²

3) Volume= BH = 120*10 = 1200 cm³