To solve the proportion \( \frac{15}{2} = \frac{75}{y} \), you can use cross-multiplication.
Cross-multiply: \[ 15y = 2 \times 75 \]
Calculating the right side: \[ 15y = 150 \]
Now, divide both sides by 15 to solve for \( y \): \[ y = \frac{150}{15} \]
Calculating the division: \[ y = 10 \]
So, the solution is: \[ y = 10 \]