Numerade

Questions asked

ANSWERED

Ivan Kochetkov

Numerade educator

A survey found that 26 of 79 people who don't drink coffee often have trouble sleeping and 28 of 81 coffee drinkers often have trouble sleeping. Construct and interpret a 99% confidence interval of the difference between the proportion of non-coffee drinkers who have trouble sleeping and the proportion of coffee drinkers who have trouble of sleeping.

View Answer

ANSWERED

Ivan Kochetkov

Numerade educator

There are nine multiple-choice questions on an exam, each question having five choices (A, B, C, D, or E). Suppose the student guesses on each question (Note: there is only one correct answer per question). a) Find the probability that the student get exactly 3 correct answers. b) Find the probability that the student get at least one correct answer. c) Find the mean and standard deviation of correct answers obtained by a student

View Answer

ANSWERED

Lynn Larson

Numerade educator

The table below represents class and voting data for 100 students who filed out the questionnaire. Year in School | | Freshman | Sophomore | Junior | Senior | Graduate | Total | | :--- | :---: | :---: | :---: | :---: | :---: | :---: | | Did you vote in the student elections? Yes | 6 | 4 | 11 | 2 | 3 | 26 | | No | 1 | 11 | 29 | 28 | 5 | 74 | | Total | 7 | 15 | 40 | 30 | 8 | 100 | If a student is selected at random (from these 100 students), a) find the probability that the student is a freshman. b) find the probability that the student is a freshman or voted in the elections.

View Answer

henry b.