Question

The surface area of the rectangular box is 4128 cm' and
length and breadth are 36 cm and 24 cm respectively
height is
b.
a
20 cm
18 cm​

Answer 1

Given :

⬤ Length and Breadth of a Rectangular box are 36 cm and 24 cm .

⬤ Surface Area of Rectangular box is 4128 .

To Find :

⬤ Height of the Rectangular box .

Formula Used :

$\bf[\:{Surface\:Area\:pf\:Cuboid=2(lb+bh+hl)}\:]$

Solution :

• Length = 36 cm .
• Breadth = 24 cm .

According to the Formula :-

4128 = 2(lb + bh + hl)

4128/2 = 2(36*24 + 24*h + h*36)

2064 = 864 + 24h + 36h

2064 = 864 + 60h

2064 - 864 = 60h

1200 = 60h

1200/60 = h

20 = h

Therefore , The Height of the Rectangular box is 20 cm .

Option a) 20 cm is Correct .

Answer 2

Understanding the Question:

• Rectangular box is a cuboid.
• The Total Surface Area is 4128 cm²
• Length = 36 cm
• Breadth = 24 cm

We need to find out the height of cuboid.

Formulas used:

★ TSA of Cuboid = 2(lb + bh + hl)

Where;

¤ l is length

¤ b is breadth

¤ h is Height.

Solution:

TSA = 2(lb + bh + hl)

⇒ TSA = 2[(36 × 24) + 24h + 36h]

⇒ 4128 = 2[864 + 24h + 36h]

⇒ 4128 = 2[864 + 60h]

⇒ 4128 = 1728 + 120h

⇒ 120h = 4128 - 1728

⇒ 120h = 2400

⇒ h = 2400 ÷ 120

∴ h = 20 cm

So, the height of the Rectangular box is 20 cm