Please answer each question sepretly.

1.Find the z-score for x = 8 if the mean is 7 and the standard deviation is 2.     

2.Find the percentile for x = 8 if the mean is 7 and the standard deviation is 2.   

3. For a mean of 20 and standard deviation of 5, find  .   

4. For a mean of 75 and a standard deviation of 3, find .  

5. For a mean of 153 and standard deviation of 25, find .  

6. IQ scores of people around the World are normally distributed, with a mean of 100 and a standard deviation of 15. A genius is someone with an IQ greater than or equal to 140. What percent of the population is considered genius? 

 7. The Weights of 100 remote control cars at a competition are approximately normally distributed. The average weight is 3.2 kg, with a standard deviation of 0.4 kg. 

I) How many remote control cars would be disqualified if it were against the rules to have a car with a weight of more than 4 kg or less than 2.4 kg? 

II) A car is said to be in the 90th percentile.  How much does it weigh? 

 

 

3 years ago

Answered By Sara S

Please retype 3, 4, and 5. 

The questione is not complete.

Thanks!

 

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