A period of four months' hair growth refers to the hair's elongation over a period of four months. For example, if an individual has hair that is 6 inches long at the start of a four-month period, it is likely to reach a length of 9 to 12 inches at the end of that period, assuming an average hair growth rate of 1.25 cm per month.
Determining the rate of hair growth over four months is significant as it can provide insights into an individual's overall hair health and can be influenced by factors such as genetics, nutrition, and hair care practices. Moreover, tracking hair growth over time allows individuals to assess the effectiveness of hair care treatments or products.