Data Collected by Child Development Scientists Produced the Following $90 \%$

question 10

Multiple Choice

Data collected by child development scientists produced the following $90 \%$ confidence interval for the average age (in months) at which children say their first word: $10.6 < \mu ($ age $) < 13.7$ .

• A) Based on this sample, we can say, with \(90 \%\) confidence, that the mean age at which children say their first word is between \(10.6\) and \(13.7\) months.
• B) \(90 \%\) of the children in this sample said their first word when they were between \(10.6\) and \(13.7\) months old.
• C) We are \(90 \%\) sure that a child will say his first word when he is between \(10.6\) and \(13.7\) months old.
• D) We are \(90 \%\) sure that the average age at which children in this sample said their first word was between \(10.6\) and \(13.7\) months.
• E) If we took many random samples of children, about \(90 \%\) of them would produce this confidence interval.

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