After the discount of 25%, Shaun will have to pay 187.50 for the shirt. 
Here's how the calculation works: 
- 25% of 250 is (25/100)*250 = 62.50 
- Shaun will get a discount of 62.50 on the shirt 
- Therefore, the amount Shaun will have to pay after the discount is 250 - 62.50 = 187.50