3.4

5 The z-score for the 34- week gestation period baby is -.0.3030. The z-score for the 40- week gestation period baby is -0.4255. The 40- week gestation period baby weights less relative to the gestation period.

7 The 75 inch man is relatively taller because its zscore of 1.8 is more than the woman’s z-score of 1.5525.

9 Kershaw had the better year when compared with his peers because his z-score was -2.302, while Kershaw’s z-score was only -1.913.

11 Ryan is better at the 100-meter backstroke because his score was -3.388, while his z-score for the 200-meter backstroke was -3.050.

13 To be 1.5 standard deviations above the mean, the minimum score that an applicant must make on the test to be accepted is 239.

15

  1. 15% of males aged 3-5 months have a head circumference that is equal to or less than 41.0 cm. 85% of males in the same age group have a head circumference that is greater than 41.0 cm.

  2. 90% of females 2 years of age have a waist circumference that is equal to or less than 52.7 cm. 10% have a wasit circumference that is grater than 52.7cm.

  3. The younger the man, the taller they are.

22

  1. (hint the mean = 10.08, standard deviation = 1.885), The z-score of Blackie is -1.21. This means that Blackie’s hemoglobin is 1.21 standard deviations below the average.

  2. Quartile 1= 8.8, Quartile 2= 9.95, Quartile 3= 11.45

  3. The IQR = 2.65

  4. The lower fence is 4.825. The upper fence is 15.425. There are no outliers.

25 The cutoff point is 574.25 minutes. This is because the IQR is 56.5, quartile 1 equals 433, and quartile 3 equals 489.5.

3.5

3

  1. The distribution is skewed right.

  2. Minimum= 0, Q1= 1, Median= 3, Q3= 6, Maximum= 16

4

  1. The distribution is symmetric.

  2. Minimum= 0, Q1= 2, Median= 5, Q3= 8, Maximum= 11

5

  1. The median of variable x is 40.

  2. The 3rd quartile of variable y is 53.

  3. Variable y has more dispersion because the lines on the box plot are more spread out.

  4. Variable x is symmetical because the median is in the center of the box and the whiskers are the same size.

  5. Variable y is skewed right because the median is closer to the left side of the box and the right whisker is longer than the left.

6

  1. The median of variable x is 16.

  2. The first quartile of variable y is 22.

  3. Variable y has more dispersion because it covers more numbers on the number line.

  4. Variable x has one outlier at 29.

  5. Variable y is skewed left becaue the median is closer to the right side of the box and the left whisker is longer than the right.

7

dat1 <- c(60,68,77,89,98)

boxplot(dat1)

8

dat2 <- c(110,140,157,173,205)

boxplot(dat2)

9

dat3 <- c(42,43,46,46,47,
         47,48,49,49,50,
         50,51,51,51,51,
         52,52,54,54,54,
         54,54,55,55,55,
         55,56,56,56,57,
         57,57,57,58,60,
         61,61,61,62,64,
         64,65,68,69)

  1. Minimum= 42, Q1= 50.5, Median= 54.5, Q3= 57.5, Maximum= 69

boxplot(dat3)

  1. The distribution is slightly skewed left because the median leans slightly towards the 3rd quartile. There is also one outlier at 69.

10

dat3 <- c(7.2, 7.8, 7.8, 7.9, 8.1, 8.3,
          8.5, 8.6, 8.6, 8.6, 8.7, 8.8,
          9.0, 9.1, 9.2, 9.2, 9.2, 9.4,
          9.4, 9.6, 9.7, 9.7, 9.9, 9.9,
          10.0, 10.0, 10.0, 10.1, 10.2, 10.3,
          10.0, 10.3, 10.3, 10.7, 10.7, 10.9,
          11.2, 11.2, 11.2, 11.3, 11.3, 11.3,
          11.5, 11.5, 11.7, 12.4, 12.5, 13.6,
          13.8, 14.4, 16.4)

  1. Minimum= 7.2, Q1= 9.0, Median= 10.0, Q3= 11.2, Maximum= 16.4

boxplot(dat3)

  1. Variable y is skewed right because the median is closer to the left side of the box and the right whisker is longer than the left.