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# 5.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, the circumference of a circle can be obtained by using the expression C = $$2\pi r$$, where r is the radius of the circle.

(a)Distance covered by the ant to take a round:
$$=\frac{1}2\times2\pi r+2r$$

$$=\pi r+2r$$

$$=\frac{22}7\times1.4+2\times1.4$$

$$=22\times 0.2+2.8$$

$$=4.4+2.8=7.2cm$$

(b)Distance covered by the ant to take a round:
$$=\frac{1}2 \times 2\pi r+1.5+1.5+2.8$$

$$=\pi r+5.8$$

$$=\frac{22}7\times 0.2+5.8$$

$$=4.4+5.8$$

$$=10.2cm$$

(c)Distance covered by the ant to take a round:
$$=\frac{1}2 \times 2\pi r+2+2$$

$$=\pi r+4$$

$$=\frac{22}7\times 1.4+4$$

$$=4.4+4$$

$$=8.4cm$$

So, among all the given paths, in path (b) ant has to travel a larger distance for food piece than others.