If a mirror is placed on the line MN, then which of the answer figures is the right image of the given figure?

The figure may be labelled as shown.

The simplest triangles are BFG, CGH, EFM, FMG, GMN, GHN, HNI, LMK, MNK and KNJ i.e. 10 in number.

The triangles composed of three components each are FAK and HKD i.e. 2 in number.

The triangles composed of four components each are BEN, CMI, GLJ and FHK i.e. 4 in number.

The triangles composed of eight components each are BAJ and OLD i.e. 2 in number.

Thus, there are 10 + 2 + 4 + 2 = 18 triangles in the given figure.

In each step, all the elements move to the adjacent corner (of the square boundary) in an ACW direction. Also, the elements that reach the lower-right and upper-left positions get vertically inverted alternately.

The figure may be labelled as shown.

There are 13 circles in the given figure. This is clear from the adjoining figure in which the centres of all the circles in the given figure have been numbered from 1 to 13.