Power prep strokes

[parallel_chase]

A certain clock marks every hour by striking a number of times equal to the hour and the time required for a stroke is exactly equal to the time interval between strokes. At 6:00 the time lapse between the beginning of the first stroke and the end of the last stroke is 22 seconds. At 12:00, how many seconds lapse between the beginning of the first stroke and the end of the last stroke?

72
50
48
46
44
[spoiler]
OA 46[/spoiler]

[callmemo]

Time required for a stroke = 22/(6+5) = 2

at 12, it'll take 2*12 + 11 * 2 = 46

[parallel_chase]

Time required for a stroke = 22/(6+5) = 2

at 12, it'll take 2*12 + 11 * 2 = 46

With this I got the gist of the entire thing, pls correct me if you think i am wrong in my reasoning

Intervals = I
Strokes = S
S-I-S-I-S-I-S-I-S-I-S
I = 5
S = 6
I + S = 11

at 6:00 - 22 seconds

22/11 = 2 (S+I)

at 12 = 12 strokes + 11 intervals
12+11 = 23

23*2 = 46

Thanks.