Answer:
 When Thomas visits the coffee shop 13 times than the change in his paycheck be is $19.5 .
Explanation:
As given 
Thomas works for a company that occupies a large campus. 
Every workday, he orders a cup of coffee on campus, and the $1.50 cost is automatically deducted from his paycheck.
 If Thomas visits the coffee shop 13 times .
Thus 
Net change in Thomas paycheck = 13 × Cost per deduction from paycheck
Put all the values in the above 
Net change in Thomas paycheck = 13 × 1.50 
 = $ 19.5
Therefore when Thomas visits the coffee shop 13 times than the change in his paycheck be is $19.5 .