Meningiomas: Demographic profile of patients diagnosed with intracranial meningiomas is studied in two academic hospitals in Johannesburg, South Africa. The following table gives the relativefrequency distribution of intracranial meningiomas Diagnosis Glioma Myeloma Meningioma Pituitary adenoma Frequency 0.27 0.02 0.41 0.30 A simple random sample gives the following frequency distribution.

Diagnosis Glioma Myeloma Meningioma Pituitary adenoma Frequency 400 200 500 100

a. Identify the population and variable under consideration here.

b. At the 5% significance level, do the data provide sufficient evidence to conclude that meningiomas were more in frequency among Black Africans?