Question 1134500: According to a government study among adults in the 25- to 34-year age group, the mean amount spent per year on reading and entertainment is $1,875. Assume that the distribution of the amounts spent follows the normal distribution with a standard deviation of $640. (Round your z-score computation to 2 decimal places and final answers to 2 decimal places.)
What percent of the adults spend more than $2,775 per year on reading and entertainment?
What percent spend between $2,775 and $3,175 per year on reading and entertainment?
What percent spend less than $1,075 per year on reading and entertainment?
Answer by Boreal(15235)   (Show Source):
You can put this solution on YOUR website! z=(x-mean)/sd
>2775 is z>(2775-1875)/640 or z> 900/640 or 1.41. This is probability of 0.0793 or 0.08
>3175 is z>1300/640 or 2.03. Probability of z between 1.41 and 2.03 is 0.0581 or 0.06
<1075 is z<(-800/640) or < -1.25 and a probability of 0.1056 or 0.11
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