Question

3. The length, breadth and
height of a cuboid are 15 m, 6
m and 5 dm respectively. The
lateral surface area of the
cuboid is​

Answer 1

Answer:

Find the volume of a cuboid whose

(i) length = 12 cm, breadth = 8 cm, height = 6 cm

(ii) length = 1.2 m, breadth = 30 cm, height = 15 cm

(iii) length = 15 cm, breadth = 2.5 dm, height = 8 cm.

Solution:

(i) The given details are:

Length of a cuboid = 12 cm

Breadth of a cuboid = 8 cm

Height of a cuboid = 6 cm

By using the formula

Volume of a cuboid = length × breadth × height

= 12 × 8 ×6

= 576 cm3

(ii) The given details are:

Length of a cuboid = 1.2 m = 120 cm

Breadth of a cuboid = 30 cm

Height of a cuboid = 15 cm

By using the formula

Volume of a cuboid = length × breadth × height

= 120 × 30 × 15

= 54000 cm3

(iii) The given details are:

Length of a cuboid = 15 cm

Breadth of a cuboid = 2.5 dm = 25 cm

Height of a cuboid = 8 cm

By using the formula

Volume of a cuboid = length × breadth × height

= 15 × 25 × 8

= 3000 cm3

Answer 2

Given :-

• The length, breadth and height of a cuboid are 15 m, 6 m and 5 dm respectively

To find :-

• Lateral surface area of cuboid

Solution :-

• Length of cuboid = 15m

• Breadth of cuboid = 6 m

• Height of cuboid = 5 dm

→ 1 m = 10dm

→ Height of cuboid = 5/10 = 0.5 m

As we know that

→ Lateral surface area of cuboid = 2(l + b)h

Where " l " is length, " b " is breadth of cuboid and " h " is height of cuboid.

According to question

→ Lateral surface area of cuboid

→ 2(l + b)h

Substitute all values of l, b and h

→ 2(15 + 6) × 0.5

→ 2 × 21 × 0.5

→ 42 × 0.5

→ 21 m²

Hence,

• Lateral surface area of cuboid is 21m²