The question I am stuck on is:

Can we calculate the mean (average) reading level of patients given the data?

I said "no, there are 6 observations we cannot count because they do not include the reading levels before grade 3 and after grade 12."

That was incorrect. I don't know how to proceed now. I have pasted all of the data from the question to help. Please help me understand how to answer this question.

"A study was done in order to find out whether pamphlets containing information for cancer patients are written at a level that the cancer patients can understand. Tests were administered to measure the reading levels of 63 cancer patients, and the readability levels of 30 cancer pamphlets were evaluated based on such factors as the lengths of the sentences and the number of polysyllabic words. Both the reading and readability levels correspond to grade levels, but patients' reading levels of less than grade 3 and above grade 12 cannot be determined exactly. (Source: Short, Moriarty, and Cooly. (1995). "Readability of Educational Materials for Cancer Patients." Journal of Statistics Education, v.3, n.2)

The following tables indicate the number of patients at each reading level and the number of pamphlets at each readability level.

Patients' Reading Level	<3	3	4	5	6	7	8	9	10	11	12	>12
Count	6	4	4	3	3	2	6	5	4	7	2	17

Pamphlets' Readability Level	6	7	8	9	10	11	12	13	14	15	16
Count	2	3	9	4	1	1	4	2	1	2	1

Note: For both the reading level and readability level, the data are presented in a grouped form where the count represents the frequency of occurrence of that level. In the readability data, for example, the count of level 6 is 2 which means that the first two data points are 6 and 6 ; the count of level 7 is 3 which means that the next three data points are 7, 7, and 7; the count of level 8 is 9 which means that the next nine data points are 8, 8, 8, 8, 8, 8, 8, 8, and 8, and so on."