Question

explain the meaning of the accompanying percentiles.
(a) the 10th percentile of the head circumference of males 3 to 5 months of age in a certain city is 41.5 cm.
(b) the 90th percentile of the waist circumference of females 2 years of age in a certain city is 52.7 cm.
(c) anthropometry involves the measurement of the human body. one goal of these measurements is to assess how body measurements may be changing over time. the following table represents the standing height of males aged 20 years or older for various age groups in a certain city in 2015. based on the percentile measurements of the different age groups, what might you conclude?
click the icon to view the data table for part c.

(a) explain the meaning of \the 10th percentile of the head circumference of males 3 to 5 months of age in a certain city is 41.5 cm.\ choose the correct answer below.
a. 90% of 3- to 5-month-old males have a head circumference that is 41.5 cm or less.
b. 10% of males have a head circumference that is 41.5 cm or less.
c. 10% of 3- to 5-month-old males have a head circumference that is 41.5 cm or more.
d. 10% of 3- to 5-month-old males have a head circumference that is 41.5 cm or less.

(b) explain the meaning of \the 90th percentile of the waist circumference of females 2 years of age in a certain city is 52.7 cm.\ choose the correct answer below.
a. 10% of 2-year-old females have a waist circumference that is 52.7 cm or less.
b. 90% of 2-year-old females have a waist circumference that is 52.7 cm or less.
c. 90% of females have a waist circumference that is 52.7 cm or less.
d. 90% of 2-year-old females have a waist circumference that is 52.7 cm or more.

Explanation:

For part (a): A percentile value indicates that a given percentage of the specific population falls at or below that measurement. Here, the 10th percentile applies to 3-5 month-old males, so 10% of this group have a head circumference of 41.5 cm or less.
For part (b): The 90th percentile means 90% of the specified population (2-year-old females) have a measurement at or below the given value, so 90% of this group have a waist circumference of 52.7 cm or less.

Answer:

(a) D. 10% of 3- to 5-month-old males have a head circumference that is 41.5 cm or less.
(b) B. 90% of 2-year-old females have a waist circumference that is 52.7 cm or less.