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how many times do the hands of a clock overlap in 12 hours

In all competitive exams questions on clock are common
At what time the hands of a clock be together?. The explanation for this question is
Given in below table shows " How many times will the hands of a clock coincide in a day? "
.
Sl No
Hours
Fraction part
Fraction part simplified
Time when the hands of a clock meet together
1
1-2
60/11
5    5/11
5    5/11 min past 1
2
2-3
120/11
10  10/11
10  10/11 min past2
3
3-4
180/11
16   4/11
16   4/11 min past 3
4
4-5
240/11
21  9/11
21   9/11 min past 4
5
5-6
300/11
27  3/11
27   3/11 min past 5
6
6-7
360/11
32  8/11
32   8/11 min past 6
7
7-8
420/11
38  2/11
38   2/11 min past 7
8
8-9
480/11
43  7/11
43   7/11 min past  8
9
9-10
540/11
49  1/11
49   1/11 min past 9
10
10-11
600/11
54  6/11
54   6/11 min past 10
11
11-12
660/11
60
60 min past 11 *
·         60 min past 11 o’ clock means 12 o’clock

In the above table the second column denotes the hours where,in between the clock hands meet together. The most important column in above table is third column which named as 'fraction part'
in first row fraction part, numerator is 60,denominator is 11. from second column onwards in the numerator fraction part,we need to add 60. Then we will get 60,120,180,240,300,360,420,480,540,600,660 in numerator of fraction part.
                     In the fourth column fraction part is simplified.
last column of the table shows the "time when the hands of clock together or overlap"
in the last column of "time when the hands of clock together or cverlap" is "60 min past 11" means it is 12 o'clock.

Observation: By seeing above table in 12 hours the hands of a clock will overlap together  11 times. 
This is important point in competitive exams.
many times it is common interview question

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