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Tagged: PROBLEM ON REFLECTION
<p>The time shown by a digital clock at 21: 15 has the curious property that it reads exactly the same after reflection in a vertical mirror. How many such times are there in the course of 24 hour clock.</p>
From the image you can see 2' s reflection is 5 / 1's reflection is 1 / 8's reflection is 8 / 0's reflection is 0.
so you have to make a 4 digit number with the digits 2,5,8,1,0 such that the reflections are in symmetric position.
Now make different cases.
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