Thank you for the opportunity to help you with your question!

start by multiplying 82% times the total number of people, which gives 82 % ∗ 15 = 0.82 ∗ 15 =
12.3
(the index). Rounding up to the nearest
whole number, you get 12

Counting from left to right (from the smallest to the largest value in
the data set), you go until you find the 12th value in the data set. That's it!

Please let me know if you need any clarification. I'm always happy to answer your questions.