Question

finally, determine the cumulative frequencies of each class for the final column of our frequency table.
recall that cumulative frequency for a class is the sum of the frequencies for that class and all previous classes.
complete the table.

class limits	frequency	relative frequency	cumulative frequency
39 – 49	21	0.42	7 + 21 = \boxed{}
50 – 60	19	0.38	\boxed{}
61 – 71	1	0.02	\boxed{}
72 – 82	2	0.04	\boxed{}

Explanation:

Step1: Calculate cumulative frequency for 39 - 49

Cumulative frequency is sum of current and previous frequencies. For 39 - 49, it's \(7 + 21\).
\(7 + 21 = 28\)

Step2: Calculate cumulative frequency for 50 - 60

Use previous cumulative frequency (28) and add current frequency (19).
\(28 + 19 = 47\)

Step3: Calculate cumulative frequency for 61 - 71

Use previous cumulative frequency (47) and add current frequency (1).
\(47 + 1 = 48\)

Step4: Calculate cumulative frequency for 72 - 82

Use previous cumulative frequency (48) and add current frequency (2).
\(48 + 2 = 50\)

Answer:

For 39 - 49: 28
For 50 - 60: 47
For 61 - 71: 48
For 72 - 82: 50