Among the 50 students in a class, what percentage of students like biology and chemistry.
Simplify : \( \large\frac{0.728 \times 0.728 - 0.272 \times 0.272}{0.456} \)
If \( \large\frac{x}{y} =\frac{3}{5} \), then \( \large\frac{5x+2y}{5x - 2y}\) is equal to