# statistics

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if a data se has a mean of 10.0 seconds & a standard deviation of 2.0 seconds, what is the z score corresponding to the time of 4.0 seconds?

• statistics -

z-score(4s) = (4-10)/2

• statistics -

Z = (score-mean)/SD

Insert values and calculate.

• statistics -

A particular statistician knows that approximately 35% of people do not tell the truth when polled. If 400 people were polled in a survey, how many would be expected to answer before someone answers untruthfully?

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