Question

a hall is 12m long and 5m high and its bredth is 2/3 of its height find the volume of the hall and total area of its four walls

Answer 1

12 x 12 x ¾ x 5
L x B x h
480m³

Answer 2

Given that l = 12 m
                h = 5 m
                b = 2/3 * h = 2/3 * 5 = 10/3 m

Now volume of this cuboid = lbh
                                           = 12 * 10/3 * 5
                                           = 200 m^3

Now area of walls is nothing but LSA of cuboid
LSA = 2h(l+b)
        = 2(5)(12+10/3)
        = 10(46/3)
        = 460/3 = 153.333 m^2
Hence area = 153.34 m^2     (aprox)

HOPE IT HELPS
ALL THE BEST!