Answer :

So in this problem we can state that each T-shirt costs S19 each. And if Kate buys two she gets a 30% off with the second shirt she buys. And how much will she pay?

Solution:

1.      
19 for each t-shirt

2.      
Total of $38 if not provided with 30% off

3.       19 x 0.3 = 5.7
4.       Hence 30% of $19 is $5.7
5.       Next is we deduct $5.7 which is 30% of $19.
6.      
19 – 5.7 = $13.3

7.      
Therefore we add one shirt for $19 and the second, less 30% off which now only costs for $13.3.

8.      
19 + 13.3 =  32.3

9.       Conclusively, she will pay $32.3 for the shirts.