How old are women when they have their first child? The table displays the distribution of the age of the mother for all firstborn children in the United States in 2014.

Age Count

10to14years 2,769

15to19years 205,747

20to24years 445,523

25to29years 428,762

30to34years 326,391

35to39years 114,972

40to44years 23,941

45to49years 2,169

The number of firstborn children to mothers under10or over50years of age represent a negligible percentage of all first births and are not included in the table.

(a) For comparison with other years and with other countries, we prefer

a histogram of the percents in each age class. A histogram of the percents in each age class is best to use for comparison with other years and other countries because a histogram can only be made using percents.

a histogram of the percents in each age class. A histogram of the percents in each age class is best to use for comparison with other years and other countries because if different years and countries have very different numbers of babies born, the distributions across age group will be difficult to compare because the scale will be determined by the larger counts.

a histogram of the counts in each age class. A histogram of the counts in each age class is best to use for comparison with other years and other countries because if different years and countries have very different percentages of babies born, the distributions across age group will be difficult to compare because the scale will be determined by the larger percentages.

a histogram of the counts in each age class. A histogram of the counts in each age class is best to use for comparison with other years and other countries because a histogram can only be made using counts.

(b) How many total firstborn babies were there? (Enter you answer rounded to the nearest whole number.)

firstborn babies=

(c) By hand, make a histogram and using this histogram select the correct description of the age at which women have their first child.

The distribution is?

(d) In which age classes do the median and quartiles fall in the ordered list of all maternal ages?

Median falls within?

1falls within?

3falls within?