Answer:
Area of 1 st rectangle, length = 10m and breath = 15m
So using formula , rectangle = length × breadth
= 10 m × 15 m
=150^{2}
again,
Area of 2 st rectangle, length = 6m and breath = 4m
So using formula , rectangle = length × breadth
= 6 m × 4 m
= 24m^{2}
Now ,
Final area of whole box = 1^{st} area - 2^{nd} area
= 150m^{2} - 24m^{2}
= 126 m^{2} is answer
