Question

In: Statistics and Probability

A recent study indicated that 30% of teenagers have cooked family dinner in the past month....

A recent study indicated that 30% of teenagers have cooked family dinner in the past month. In a random sample of 20 teenagers, what is the probability that...

...exactly 6 have cooked dinner in the past month? (round your answer to 3 decimal places)

...fewer than 4 have cooked dinner in the past month? (round your answer to 3 decimal places)

...at least 9 but no more than 12 have cooked dinner in the past month? (round your answer to 3 decimal places) Did you use a table, calculator, or formula for your answers above? (Make sure your submitted work confirms your method).

Expert Solution

The number of teenagers who have cooked family dinner in the past month out of the 20 teenagers sample is modelled here as:

a) The probability that exactly 6 have cooked dinner in the past month is computed here as:

Therefore 0.192 is the required probability here.

b) The probability that fewer than 4 have cooked dinner in the past month is computed here as:

Therefore 0.107 is the required probability here.

c) The probability that at least 9 but no more than 12 have cooked dinner in the past month is computed here as:

Therefore 0.112 is the required probability here.

orchestra answered 2 years ago

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