To calculate the overall star rating and percentage breakdown by star, we don’t use a simple average. Instead, our system considers things like how recent a review is and if the reviewer bought the item on Amazon. It also analyses reviews to verify trustworthiness.
My daughter is a VERY small 11 year old and 10-12 seemed reasonable. She can only wear it under a tank top since the sides of the front nearly expose her non-existent chest. The fabric is thin, but overall I guess the product is what you pay for and at less than $3, it's not terrible and an ok backup until her new one arrives.