Question

Find the total surface area of cuboids, given the following measures (i) L = 4 m. b = 3 m, h = 2 m (ii) L= 12 cm. b=8 cm, h = 6 cm (iii) L= 40 cm, b = 25 cm, h = 15 cm (iv) L= 3.6 cm b=3 cm, h=1.5 cm find . o​

Answer 1

Answer:

Question:-

Find the total surface area of cuboids, given the following measures

(i) L = 4 m. b = 3 m, h = 2 m

(ii) L= 12 cm b=8 cm, h = 6 cm

(iii) L= 40 cm, b = 25 cm, h = 15 cm

(iv) L= 3.6 cm b=3 cm, h=1.5 cm

Solution:-

(i) Length of cuboid=4m

Breadth of cuboid=3m

Height of cuboid=2m

Total surface area of cuboid=2(lb+bh+hl)

On substituting the values we get,

2(4m×3m+3m×2m+2m×4m)

$2(12 {m}^{2} + 6 {m}^{2} + 8 {m}^{2} )$

$2(26 {m}^{2} )$

$52 {m}^{2}$

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(ii) Length of cuboid=12cm

Breadth of cuboid=8cm

Height of cuboid=6cm

Total surface area of cuboid=2(lb+bh+hl)

On substituting the values we get,

2(12cm×8cm+8cm×6cm+6cm×8cm)

$2(96 {cm}^{2} + 48 {cm}^{2} + 48 {cm}^{2} )$

$2(192 {cm}^{2} )$

$= 384 {cm}^{2}$

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(iii) Length of cuboid=40cm

Breadth of cuboid= 25cm

Height of cuboid=15cm

Total surface area of cuboid=2(lb+bh+hl)

On substituting the given values we get,

2(40cm×25cm+25cm×15cm+15cm×25cm)

$2(1000 {cm}^{2} + 375 {cm}^{2} + 375 {cm}^{2} )$

$2(1750 {cm}^{2} )$

$= 3500 {cm}^{2}$

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(iv) Length of cuboid=3.6cm

Breadth of cuboid=3cm

Height of cuboid=1.5cm

Total surface area of cuboid=2(lb+bh+hl)

On substituting the given values we get,

2(3.6cm×3cm+3cm×1.5cm+1.5cm×3.6cm)

$2(10.8 {cm}^{2} + 4.5 {cm}^{2} + 5.4 {cm}^{2} )$

$2(20.7 {cm}^{2} )$

$41.4 {cm}^{2}$

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