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An ant is moving around a few food pieces of different shapes scattered on the floor. For which food-piece would the ant have to take a longer round? Remember, circumference of a circle can be obtained by using the expression C = 2πr, where r is the radius of the circle.



 


A. B.


 


C.


Food pieces with larger perimeter would make the ant to take the longer round.


Perimeter for Shape A:


Since, Shape A is Semi Circle.


Perimeter = πr + 2r


= (22/7) × 1.4 + 2.8


= 7.2 cm


Perimeter for Shape B:


Perimeter = Sum of length of all the outer boundary


= 2.8 + 1.5 + 1.5 + πr


= 2.8 + 1.5 + 1.5 + (22/7) × 1.4


= 10.2 cm


Perimeter for Shape C:


Perimeter = Sum of length of all the outer boundary


Perimeter = 2 + 2 + πr


Perimeter = 2 + 2 + (22/7) × 1.4


= 8.4 cm


Perimeter is maximum for shape B, So Ant wiould have to take the longer round for Shape B.

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