The length and breadth of a cuboidal store are in the ratio 2 : 1 and its height is 3.5 metres. If the area of its four walls (including doors) is 210 m², then its volume is ____.

700 m³

We know that,

Area of four wall = 2 (l + b) × h

The ratio of length and breadth = 2a : a

Height of the cuboidal store h = 3.5

According to the question,

2 (2a + a) × 3.5 = 210

3a = 30

x = \(\frac{30}{2}\) = 10

Volume of cuboidal store = 2a × a × 3.5 = 2 × 10 × 10 × 3.5 = 700