Ex 12.2, 1 (e) - Chapter 12 Class 7 Symmetry

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Ex 12.2, 1 (e) Which of the following figures have rotational symmetry of order more than 1: Since circle is divided into 3 equal sectors, Angle at center = (360°)/3 = 120° Let’s rotate it by 120° This figure looks same as previous Suppose it rotates 120° again This figure looks same as previous Again it rotates 120° This figure looks same as previous Thus, in 1 – full turn (i.e 360°) The figure is same as that of initial 3 turns. So, we say that figure has rotational symmetry of order 3