Correlation Coefficient
Pearson's r — strength and direction of a linear relationship.
Scatter plot (study hours vs score)
scorehours
Pearson r
0.996
Very strong positive
Formula
r = Σ(x−x̄)(y−ȳ) / √[Σ(x−x̄)² · Σ(y−ȳ)²]
numerator = 64.5, denominator = 64.8. r = 0 means no linear association — but the data could still curve.