It's likely above average for a 15-year-old.
Height varies greatly among 15-year-olds due to factors like genetics, nutrition, and overall health. However, 178 cm is generally considered taller than average for this age group.
While I cannot provide exact percentile data without knowing the individual's sex and specific population (country, ethnicity, etc.), the provided reference indicates that at a height near this at age 15, a person is likely nearing the end of their fastest growth spurt and may reach 184-187 cm as an adult. This further suggests it is an above-average height.
To get a more precise understanding, it would be best to compare this height to growth charts specific to the individual's sex and region. These charts are often available from pediatricians or online through reputable sources like the World Health Organization (WHO) or the Centers for Disease Control and Prevention (CDC).
