Part of a test given to young children consists of putting together a simple jigsaw puzzle. Suppose that such a puzzle is given to 4000 children, each child is timed, and a graph of the times is made. Suppose that the graph is a normal curve with a mean time of 120 sec and a standard deviation of 18 sec. (a) About how many of the children finished the puzzle in less than 84 sec?  children (b) How many took more than 156 sec?  children (c) If you rated as "average" all the children within 1 standard deviation from the mean, how many children would fall into this classification?  children

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A: Given problem Given that

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A: Here, µ =15 and σ = 2.7. It is required to find the age of death of middle 30% of indoor cats.

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A:

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A:

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