Consider a watch face which has identical hands and identical marks
for the hours. It is opposite to a mirror. When is the time as read
direct and in the mirror exactly the same between 6 and 7?
Using the 8 dominoes make a square where each of the columns and rows adds up to 8
The ten arcs forming the edges of the "holly leaf" are all arcs of
circles of radius 1 cm. Find the length of the perimeter of the
holly leaf and the area of its surface.
In what follows I'm going to call the design above the "unit
shape" and imagine it repeated endlessly along a line - rather like
a stream of paper coming off a roll.
Try to design a new unit shape (probably simpler than mine) to
make a strip which looks the same after a 180 $^\circ$
In other words, make it so that you could not say whether the
torn off strip had or had not been rotated.
First the original strip could have a mirror across it.
This illustration shows the right side as the reflection of the
Can you create a unit shape so that the strip has reflection
symmetry across a vertical mirror line ?
And where would the mirror line need to be to be placed ?