A researcher designs an experiment to test whether a new study technique improves exam scores compared to traditional methods. Preliminary research suggests the true effect size is Cohen's $d = 0.50$ (medium effect). The researcher wants 80% statistical power and sets $\alpha = 0.05$ (two-tailed). Using the formula:

$n = 2 \times \left[ \frac{z_{\alpha/2} + z_{\beta}}{d} \right]^2$

where $z_{\alpha/2} = 1.96$ and $z_{\beta} = 0.84$, approximately how many students are needed in each group?