everyone's menstruation cycle varies, basically the menstruation cycle is the length it takes for the lining of the uterus to break down at the start of the menstrual cycle to the end of cycle when the lining of uterus remains in place. So the average cycle can vary from women to women , As for the length of the menstrual period is concerned, like i had said above is when the lining of uterus along with some blood is passed out . it happens towards the start of the menstruation cycle. Hope that helped :)
The average cycle length is approximately 28-30 days. You start counting with the first day of your period (day 1), then start counting over again with the 1st day of your next period. About 14 days from the 1st day of your period, "mid-cycle," is around the time you ovulate; the time you're most likely to get pregnant. The average length of a period varies greatly. Could be as little as 2 days, or longer than a week. Every woman is different. Hope this helped!