Answer :

Sure, let's determine the new mean when 17 is added to the given data set.

1. Original Data Set and Mean:
The original data set is:
[tex]\[ 12, 30, 19, 27, 21, 35 \][/tex]
The mean of this data set is given as 24.

2. Calculate the Original Sum:
The mean ([tex]\( \overline{x} \)[/tex]) of a set of numbers is calculated by dividing the sum of the numbers by the count of the numbers.
[tex]\[ \overline{x} = \frac{\sum x_i}{n} \][/tex]
Here, [tex]\( \overline{x} = 24 \)[/tex] and [tex]\( n = 6 \)[/tex] (since there are 6 numbers in the original data set).

To find the original sum ([tex]\( \sum x_i \)[/tex]):
[tex]\[ 24 = \frac{\sum x_i}{6} \][/tex]
Multiplying both sides by 6 gives:
[tex]\[ \sum x_i = 144 \][/tex]

3. Add the New Value to the Sum:
Now, we add the new value (17) to the original sum:
[tex]\[ \text{New Sum} = 144 + 17 = 161 \][/tex]

4. Determine the New Count of Numbers:
Initially, there were 6 numbers. By adding one more number, the new count becomes:
[tex]\[ n_{\text{new}} = 6 + 1 = 7 \][/tex]

5. Calculate the New Mean:
Using the new sum and the new count of numbers, the new mean ([tex]\( \overline{x}_{\text{new}} \)[/tex]) is:
[tex]\[ \overline{x}_{\text{new}} = \frac{161}{7} \][/tex]

6. Simplify the New Mean:
Performing the division:
[tex]\[ \overline{x}_{\text{new}} = 23.0 \][/tex]

So, the new mean after adding 17 to the data set is 23.0.