A random number generator is set to generate single digits ...

[tatyanajohnson]

A random number generator is set to generate single digits between 0 and 9. One hundred and fifty random numbers are generated.
 
  The probability distribution for this random number generator is given below. What is the mean of this distribution?
 
  x 0 1 2 3 4 5 6 7 8 9
  P(x) 0.09 0.12 0.11 0.08 0.09 0.13 0.10 0.07 0.10 0.11
 
  A) 6.6 B) 4.5 C) 7 D) 5

Question 2

Geologists have an interest in the structure and the history of the earth. A geologist can go back in time by drilling deep into the ground, retrieving a core sample, estimating the ages of the various layers, and examining the composition.
 
  A timeline can be built of the entire area from where the core sample was drilled. A geologist may retrieve several core samples to confirm the history of the earth's structure in that sampled area. Mountains, lakes, and unstable ground can easily impede a simple random sampling of a desired geographical area, therefore what is the most realistic sampling method that represents the actual drillings, comparisons, and scientific examinations of several core samples within the same geographical area?
  A) Systematic sampling B) Cluster sampling
  C) Multistage sampling D) Stratified sampling

[s.meritte]

Answer to Question 1

B

Answer to Question 2

B

[tatyanajohnson]

Excellent

[marict]

Gracias!