The length and breadth of a painting are 15cm and 10cm respectively. A 1cm wide border is made around the painting. What is the area of the border?

1. Calculate the area of the inner painting:
Area
inner
​
=length×breadth=15cm×10cm=150sq cm
Determine the dimensions of the outer rectangle (painting + border):
Since a 1cm wide border is added all around, the length and breadth increase by 1cm on both sides (left/right and top/bottom).

Outer Length=15+1+1=17cm
Outer Breadth=10+1+1=12cm
Calculate the area of the outer rectangle:

Area
outer
​
=17cm×12cm=204sq cm
Calculate the area of the border:

Area of border=Area
outer
​
−Area
inner
​

Area of border=204−150=54sq cm
Thus, the area of the border is 54sq cm.