A certain clock marks every hour by striking a number of times equal to the hour and the time required a stroke is exactly equal to the time interval between the strokes. At 6 the time elapse between the begining of the first stroke and teh end fo the last stroke is 22 sec. At 12, how many seconds elaspse between the beginning of first stroke and the end of the last stroke?
A 72
B 50
C 48
D 46
E 44
Can you please "mathematicize" the underlined and show the setup and the answer for this question? I am not satisfied with OG's explanation.
Thank you,