To solve the problem, we start with the given equation of the line of best fit:
[tex]\[ y = 2.5x - 1.5 \][/tex]
We need to predict the value of [tex]\( y \)[/tex] when [tex]\( x = 3 \)[/tex].
Step-by-step:
1. Substitute [tex]\( x = 3 \)[/tex] into the equation:
[tex]\[ y = 2.5(3) - 1.5 \][/tex]
2. Calculate [tex]\( 2.5 \times 3 \)[/tex]:
[tex]\[ 2.5 \times 3 = 7.5 \][/tex]
3. Subtract 1.5 from 7.5:
[tex]\[ y = 7.5 - 1.5 \][/tex]
[tex]\[ y = 6 \][/tex]
Thus, the predicted value of [tex]\( y \)[/tex] when [tex]\( x = 3 \)[/tex] is [tex]\( 6 \)[/tex].
Therefore, the correct answer is:
[tex]\[
\boxed{6}
\][/tex]
