Approximate the median of the frequency distribution in Problem 1.

Weight (grams) ....Number of Babies (thousands)

0-999 ........ 30

1000-1999 ...... 97

2000-2999 ....... 935

3000-3999 .......2698

4000-4999 ....... 344

5000-5999 ....... 5

Use the following steps to approximate the median from grouped data.

Approximating the Median from Grouped Data

Step I Construct a cumulative frequency distribution.
Step 2 Identify the class in which the median lies. Remember, the median can be obtained by determining the observation that lies in the middle.

Step 3 Interpolate the median using the formula

where
L is the lower class limit of the class containing the median
n is the number of data values in the frequency distribution
CF is the cumulative frequency of the class immediately preceding the class containing the median
f is the frequency of the median class
i is the class width of the class containing the median

Transcribed Image Text:

rt - CF Median = M = L + (i)