Question

a researcher for the epa measured the amount of arsenic in the water near a sewage treatment plant. over 12 days, he took ( n = 40 ) measurements (in ppb). his sample data is summarized in the frequency distribution polygon shown below. how many measurements taken in this time frame were within ( 50,55) ) ppb? ans = question help: message instructor submit question

Explanation:

Step1: Identify the value on the y - axis for the interval [50,55)

The x - axis represents the arsenic levels (in ppb), and the y - axis represents the frequency (number of measurements).

Step2: Read the frequency value

Looking at the frequency distribution polygon, for the interval [50,55) ppb, the corresponding y - value (frequency) is 4.

Answer:

4