Question

A closed rectangular box is made of wood of $1.5$ cm thickness. The exterior length and breadth are respectively $78$ cm and $19$ cm, and the capacity of the box is $15$ cubic decimeters. Calculate the exterior height of the box.

• A. $15.5$ cm
• B. $25.5$ cm
• C. $30$ cm
• D. $19$ cm

Answer 1

Answer: (A)

$15.5$ cm

Interior dimension are

$78-3=75$cm

$19-3=16$cm

& $h=3$

Interior Volume $=75\times 16\times (h-3)$

$\Rightarrow 15000{cm}^3=75\times 16\times (h-3)$

$\Rightarrow (h-3)=\frac{15000}{75\times 16}=12.5cm$

$\Rightarrow h=12.5+3=15.5cm$

$\therefore$ Exterior height of box $=15.5$cm