The 5-number summary for test # 2 is 18.4, 52.8, 59, 65.5, and 84.1. What is the left whisker?

The 5-number summary for test # 2 is 18.4, 52.8, 59, 65.5, and 84.1. What is the left whisker? 

Selected Answer:46.45

IQR=65.5-52.8=12.7

12.7*1.5=19.05

Q3-1.5IQR

65.5-19.05=46.45

Got this answer wrong on a practice quiz. Please help.