Question

a rectangular water reservoir contains 42000 litres of water .find the depth of the water if its base measures 6m by 3.5m

Answer 1

Given length of the rectangular reservoir [cuboid] = l = 6m
Breadth = b = 3.5m
Let the Depth(height) of the cuboid be `h`
Given volume = 42000 litre = 42m³
We know that the volume of a cuboid = lbh
⇒6m × 3.5m × `h`m = 42m³
⇒21h m³ = 42m³
⇒h = 42m³/21m³
∴h = 2m
∴The depth of the reservoir is 2m

Answer 2

as we know that, 1000 L = 1 m³
so, 42000 L = 42 m³
now, Let the depth of water in reservoir = h m
then volume of water in reservoir = (6×3.5×h) m³
A/q,
(6×3.5×h) =42
⇒ h= 42/21
      =2 m
∴depth of reservoir is 2 m