Question

1.Find the volume surface area and the total surface area of the cuboid whose dimension are:
(i)length=15cm,breadth=6cm and height=9dm​

Answer 1

AnswEr :

• G I V E N ⠀D I M E N S I O N S :

◗ Length = 15 cm

◗ Breadth = 6 cm

◗ Height = 9 dm = (9 × 10) cm = 90 cm

1 ) Volume of Cuboid :

⇒ Volume = (Length × Breadth × Height)

⇒ Volume = (15 cm × 6 cm × 90 cm)

⇒ Volume = (90 cm² × 90 cm)

⇒ Volume = 8100 cm³

∴ Volume of Cuboid is 8100 cm³

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2 ) Surface Area :

⇒ Surface Area = 2(l + b) × Height

⇒ Surface Area = 2(15 cm + 6 cm) × 90 cm

⇒ Surface Area = 2 × 21 cm × 90 cm

⇒ Surface Area = 42 cm × 90 cm

⇒ Surface Area = 3780 cm²

∴ Surface Area of Cuboid is 3780 cm²

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3 ) Total Surface Area :

⇒ TSA = 2(lb + bh + hl)

⇒ TSA = 2[(15 × 6) + (6 × 90) + (90 × 15)]

⇒ TSA = 2[90 cm² + 540 cm² + 1350 cm²]

⇒ TSA = 2 × 1980 cm²

⇒ TSA = 3960 cm²

∴ Total Surface Area of Cuboid is 3960 cm²

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• I M P O R T A N T ⠀F O R M L A E :

1 ) Cuboid :

↠ Volume = lbh

↠ Surface Area = 2(l + b) × h

↠ TSA = 2(lb + bh + hl)

↠ Diagonal = √(l² + b² + h²)

2 ) Cube :

↠ Volume = (Side)³

↠ Surface Area = 4 × (Side)²

↠ TSA = 6 × (Side)²

↠ Diagonal = √3 Side

3 ) Cylinder :

↠ Volume = πr²h

↠ CSA = 2πrh

↠ TSA = 2πr(r + h)

4 ) Cone :

↠ Volume = 1 /3 × πr²h

↠ CSA = πrl

↠ TSA = πr(r + l)

↠ Slant Height ( l ) = √(r² + h²)

5 ) Sphere :

↠ Volume = 4 /3 × πr³

↠ Surface Area = 4πr²

6 ) Hemisphere :

↠ Volume = 2 /3 × πr³

↠ CSA = 2πr²

↠ TSA = 3πr²

#answerwithquality #BAL

Answer 2

$\huge{\underline{\underline{\red{\mathfrak{Answer :}}}}}$

✪ Given :

Height of cuboid = 90 cm = 9dm

Length of cuboid = 15 cm

Breadth of cuboid = 6 cm

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✪ To Find :

Volume, Total Surface area, Curved Surface Area

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✪ Solution :

We have formula for volume :

$\Large{\underline{\boxed{\sf{Volume \: = \: lbh}}}}$

Put Values

⇒Volume = 15*90*6

⇒Volume = 1800 cm³

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And formula for Surface Area is :

$\Large{\underline{\boxed{\sf{C.S.A \: = \: 2(l \: + \: b)h}}}}$

Put Values

⇒C.S.A = 2(15 + 6)(90)

⇒C.S.A = 2(21)(90)

⇒C.S.A = (42)(90)

⇒C.S.A = 3780 cm²

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Formula for Total Surface Area is :

$\Large{\underline{\boxed{\sf{T.S.A \: = \: 2(lb \: + \: bh \: + \: lh)}}}}$

Put Values

⇒T.S.A = 2(15*6 + 90*6 + 90*15)

⇒T.S.A = 2(90 + 540 + 1350)

⇒T.S.A = 2(1980)

⇒T.S.A = 3960 cm²

__________________________

#answerwithquality

#BAL