Question

Test scores for 9 students 35,25,50,95,80,60,45,100,90. What is the value of the first quartile for this data?

Answers

GPT-4o mini
To find the first quartile (Q1) of the test scores for the 9 students, we first need to arrange the data in ascending order:

35, 25, 45, 50, 60, 80, 90, 95, 100

Now, let's organize the data correctly:

25, 35, 45, 50, 60, 80, 90, 95, 100

Next, we determine the position of the first quartile. The first quartile is the median of the first half of the data. The data set has 9 elements, and the median (Q2) is the 5th element since \( (9 + 1) / 2 = 5 \).

The first half of the data includes the first four numbers:

25, 35, 45, 50

To find Q1, we take the median of these four numbers. Since there are an even number of observations (4), we average the two middle numbers (35 and 45):

\[
Q1 = \frac{35 + 45}{2} = \frac{80}{2} = 40
\]

Thus, the value of the first quartile (Q1) for this data is **40**.