Answer:
Step-by-step explanation:
Before answering we must clearly understand the difference between a statistic and a parameter.
The characteristic of a population is parameter. Example, population mean, population std deviation, population variances are called parameters.
Sample mean, sample std dev, sample variances are called statistics.
Here given that 7 math classes were surveyed and average was calcualted as 83%
Hence only sample mean = 83% and this is hence a statistic
If all 15 math classes surveyed and average taken that would have been the parameter.