If you pay $35 for a drug and the selling price is $50 what is the percent gross profit

1. **Determine the selling price and cost price**:
Selling Price (SP) = 50
Cost Price (CP) = 35

2. **Calculate the gross profit**:
Gross Profit = SP - CP = 50 - 35 = 15

3. **Calculate the percent gross profit**:
Percent Gross Profit = \left( \frac{15}{35} \right) \times 100 = 42.8571\%

4. **Answer**:
The percent gross profit is 42.8571\%