Answer: The percent gain was 25%.
Step-by-step explanation:
Given, Cost price of lot = $1,200
Selling price of lot = $1,500
The percent gain = [tex]\dfrac{\text{selling price- cost price}}{\text{cost price}}\times100[/tex]
⇒ Percent gain =[tex]\dfrac{1500-1200}{1200}\times100\%[/tex]
[tex]\Rightarrow\text{ Percent gain}=\dfrac{300}{1200}\times100\%\\\\\Rightarrow\text{ Percent gain}=\dfrac{1}{4}\times100\%\\\\\Rightarrow\text{ Percent gain}=25\%[/tex]
Hence, the percent gain was 25% based on his purchase.