In an experiment similar to the one you performed in Week 3, an experimenter measures the count rate of a radioactive element 100 times, calculates the mean and standard deviation of the data, and organizes the data into four bins:
Interval Number of Occurrences
n < n 15
< n < n 50 - 15
n < n < + 38
n > n + 12
The experimenter expects a Gaussian distribution. (For simplicity, assume 68 % of the counts fall within one standard deviation of the mean rather than the more exact value of 68.27 \%.) What is x?