Question

A beam 5 m long and 40 cm wide contains 0.6 cubic metre of wood. How thick is the beam?

Answer 1

\[\text { Length of the beam = 5m }\]

\[\text { Breadth = 40 cm }\]

\[ = 40 \times \frac{1}{100}m ( \because 100 cm = 1 m)\]

\[ = 0 . 4 m\]

\[\text { Suppose that the height of the beam is h m  }. \]

\[\text { Also, it is given that the beam contains 0 . 6 cubic metre of wood  }. \]

\[\text { i . e . , volume of the beam = 0 . 6  }m^3 \]

\[\text { Now, volume of the cuboidal beam = length } \times \text { breadth }\times\text {  height}\]

\[ \Rightarrow 0 . 6 = 5 \times 0 . 4 \times h\]

\[ \Rightarrow 0 . 6 = 2 \times h\]

\[ \Rightarrow h = \frac{0 . 6}{2} = 0 . 3 m\]

\[ \therefore \text { The beam is 0 . 3 m thick } .\]