Question

In a recent issue of the IEEE Spectrum, 84 engineering conferences were announced. Four conferences lasted two days. Thirty-six lasted three days. Eighteen lasted four days. Nineteen lasted five days. Four lasted six days. One lasted seven days. One lasted eight days. One lasted nine days. Let X = the length (in days) of an engineering conference.

The data is shown in the table below.


Number of Conferences

Days Lasted

4

2

36

3

18

4

19

5

4

6

1

7

1

8

1

9



Calculate the sample mean of days of engineering conferences.

Answer 1

The sample mean of the days of engineering conferences is 5.5.

Explanation:

The given data says that values of X are the length in days.

where X= 2, 3, 4, 5, 6, 7, 8, 9.

number of samples = 8.

we have to find the sample mean for the days.

Mean =
`(sum of all data)/(number of samples)`.

=
`(2+3+4+5+6+7+8+9)/(8)`.

=
`(44)/(8)`.

Mean = 5.5.

∴ The sample mean of the days is 5.5.