Answer:
Step-by-step explanation:
To find the data item that corresponds to a given z-score, we can use the formula:
z = (x - μ) / σ
where:
z is the z-score
x is the data item we're looking for
μ is the mean of the distribution
σ is the standard deviation of the distribution
In this case, we're given the values of μ and σ, and we want to find x when z = 2.5. So we can rearrange the formula to solve for x:
x = z * σ + μ
Substituting the given values, we get:
x = 2.5 * 30 + 100 = 175
Therefore, the data item that corresponds to a z-score of 2.5 in this distribution is 175.