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

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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

c

step-by-step explanation:

because of the levels

step-by-step explanation:

given perimeter: 28cm

length: 9cm

atp,

2(l+w)=p of the reactangle

2(9+x)=28

18+2x=28

2x=28-18

x=10/2

x=5

therefore width is 5 cm