How many times are the hands of a clock at $90$ degrees. 
How many times are the hands of a clock at right angle in a day? 

Initially, I worked this out to be $2$ times every hour. The answer came to $48$.
However, in the cases of $3$ o'clock and $9$ o'clock, right angles happen only once.
So the answer came out to be $44$.
Is the approach correct?





This Is situation of 12 hrs. Usually in each hour there are 2 90 deg but these two are exceptions. This repeats again and thus there are 4 exceptions. Since there must be 48 90 deg but excluding 4 exceptions there 48-4 =44  90 deg angles.
