# Statistics / Math

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If a student is chosen at random, find the probability of getting someone who is a man or a non-smoker. Round your answer to three decimal places.

non regular heavy total
man 135 64 5 204
women 187 21 9 217
total 322 85 14 421

Answer in decimal (round to nearest 3)

• Statistics / Math -

Out of a total of 421 people, of both sexes and three classifications of smoking habits, 135 were nonsmoking men. Therefore the probability is 135/421 = 0.3207

This assumes that the sampling group was representative of the larger group of people they may have been drawn from.

• Statistics / Math -

ops, 0.307 is not in the answer choices.

they are:

0.929
0.798
0.949
0.941

P.S. - Probability of getting a Man OR A Non-Smoker

• Statistics / Math -

Need help with this plzzzzzzzzzz

• Statistics / Math -

I misread the problem as man AND nonsmoker. You want man OR nonsmoker. Using the same method but more groups from the table, I get
(204 + 187)/421 = 0.929

• Statistics / Math -

Calculate the standard deviation for: 10, 20, 30 to the nearest tenth presuming a sample