Answer :

To find the measure of one interior angle of a regular 23-gon, we can use the formula for calculating the measure of an interior angle of a regular polygon. Here is the step-by-step explanation:

1. Understand the formula:
The formula to find the measure of one interior angle of a regular polygon with [tex]\( n \)[/tex] sides is:
[tex]\[ \text{Interior angle} = \frac{(n-2) \times 180^\circ}{n} \][/tex]
This formula comes from the fact that the sum of all interior angles of a polygon with [tex]\( n \)[/tex] sides is [tex]\((n-2) \times 180^\circ\)[/tex].

2. Substitute the given value:
For a 23-gon, [tex]\( n = 23 \)[/tex]. Substitute this value into the formula:
[tex]\[ \text{Interior angle} = \frac{(23-2) \times 180^\circ}{23} \][/tex]

3. Simplify the expression:
Calculate the numerator first:
[tex]\[ 23 - 2 = 21 \][/tex]
So, the numerator becomes:
[tex]\[ 21 \times 180^\circ \][/tex]
Now, calculate:
[tex]\[ 21 \times 180^\circ = 3780^\circ \][/tex]

4. Divide by the number of sides:
Next, divide this result by the number of sides, which is 23:
[tex]\[ \frac{3780^\circ}{23} \][/tex]
Perform the division:
[tex]\[ 3780^\circ \div 23 = 164.34782608695653^\circ \][/tex]

Therefore, the measure of one interior angle of a regular 23-gon is approximately [tex]\( 164.3^\circ \)[/tex].

So, the correct answer is:
D. 164.3