Joan’s finishing time for the Bolder Boulder 10K race was 1.74 standard deviations faster than the women’s average for her age group. There were 380 women who ran in her age group. Assuming a normal distribution, how many women ran faster than Joan?

The standard deviation is the average amount of variability in our data set. It tell about how far each score lies from the mean.

16 women ran faster than Joan

Since, Joan’s finishing time for the Bolder Boulder 10K race was 1.74 standard deviations faster than the women’s average for her age group.

So,  Z - score = 1.74  

From z - table, we saw that for Z = 1.74 , corresponding  p-value is 0.9591. It means that Joan was faster than 95.91% of the participants and slower than 100-95.91 = 4.09% of the participants.

Since, There were 380 women who ran in her age group.

we computed that, 4.09% faster than Joan

Number of women run faster than Joan is, = , nearly = 16

Thus, 16 women ran faster than Joan

Learn more:

link

16 women ran faster than Joan

Step-by-step explanation:

The z-score measures how many standard deviations a score X is above or below the mean.

Each z-score has its respective p-value, which is the percentile of X. We find the p-value looking at the z-table.

Joan’s finishing time for the Bolder Boulder 10K race was 1.74 standard deviations faster than the women’s average for her age group.

So

has a pvalue of 0.9591. Which means that Joan was faster than 95.91% of the participants and slower than 100-95.91 = 4.09% of the participants.

Assuming a normal distribution, how many women ran faster than Joan?

380 participants

4.09% faster than Joan

0.0409*380 = 15.5

Rounding up, 16 women ran faster than Joan

step-by-step explanation:

once you graph it hit 2nd (the blue button) and graph

that takes you to a table of coordinates

on the left is x coordinates and on the right is y coordinates and an empty box

(you may have to scroll up/down in order to get ( x, 0)

54 km / hours

step-by-step explanation:

we need to convert seconds to hours

60 seconds = 1 minutes

60 minutes = 1hour

15 m         60 second   60 minutes

  * *         = 54000 meters/ hour

second     1 minute             1 hour

now we need to convert meters to km

1000 m = 1 km

54000 m       1 km

*   = 54 km / hours

hour               1000m