A picture is painted on a cardboard 8 cm long and 5 cm wide such that there is a margin of 1.5 cm along each of its sides. Find the total area of the margin.

It is given in the question that,

Length of cardboard = 8 cm

Breadth of cardboard = 5 cm

We know that,

Area of rectangle = Length × Breadth

∴ Area of cardboard including margin = 8 × 5

= 40 cm^{2}

From the figure, it can be observed that the new length and breadth of the given cardboard (When margin is not included) is 5 cm and 2 cm respectively

∴ Area of cardboard not including margin = 5 × 2

= 10 cm^{2}

Area of the margin = Area of the cardboard including the margin – Area of cardboard not including margin

= 40 – 10

= 30 cm^{2}

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