Question

The prices paid for a model of a new car are approximately normally distributed with a mean of $17,000 and a standard deviation of $500.

The price that is 3 standard deviations above the mean is $_

The price that is 2 standard deviations below the mean is $_

The percentage of buyers who paid between $16,500 and $17,500 is __%

The percentage of buyers who paid between $17,000 and $18,000 is __%

The percentage of buyers who paid less than $16,000 is __%

Answer 1

ok so I am also a high school student so my answer may not be correct but here are the answers.

1. 18500

2. 16000

3. 68.3%

4. 47.7%

5. 2.3%

Explanation:

To find the answers to questions 1, 2, just add 500 to mean for above and substract 500 for below. I just used a graphic calculator for 3, 4 and 5.

For a casio calculator, here are the steps

menu, 2, dist, norm, ncd,

data: variable

lower: 3. 16500, 4. 17000, 5. 0

upper: 3. 17500, 4. 18000, 5. 16000

deviation: 500

Mean: 17000

Hope this helps.