I encountered a question here:

Sodium content of hot dogs are normally distributed with mean = 140 mg and standard deviation = 8 mg. If we randomly select 49 hot dogs, what is the probability that their mean sodium content will be greater than 145 mg?

I know this question can be vague, but I assumed the sodium content from 49 hot dogs follows normal distribution, so I found z score that corresponds to 145 given N(140,64) and found the probability to be 0.266.