Yup, it is 21 shirts that were large. Reason being is so:
1) You have to set up a proportion in order to solve this equation. You know that there is a total of 28 shirts that Jenna ordered BUT 75% of them were large.
As you also know, percents are ALWAYS over a 100. Using this knowledge, let's set up our proportion: [use x to represent the amount of large shirts she ordered]
x 75
-- = ------
28 100
2) To solve we will cross multiply! (First do 28 times 75, which gives you 2,100 and 100 times x, which gives you a 100 x).
As a result, you end up with:
100x= 2,100
3) Now isolate x!!!
100x=2,100
----- ------
100 100 DIVIDE into 2,100
x= 21
4) Your final answer is 21 large shirts!
