Answer: 4 Shirts
Explanation:
Given
Person has 
 
 
Pant costs 
 and shirt costs
 and shirt costs 

Suppose 
 as number of pant and shirts
 as number of pant and shirts
Spent money must be equal or less than the total money. The inequality becomes

For 1 pair of pants that is, 1 pants

That is maximum number of shirts that can be bought are 4.