Show work please

Using methods suggested in the video related to service design at "noodles \& company." Arora's restaurant reduces the average service time by 50% (i.e,, =4 minutes). As a result of this change, the average time that a customer now spends waiting in the queue is reduced by what percentage? (+13%) Note: For example, if something goes down from 5 to 4 , it is termed as a reduction of 20%. A. 50% B. 90% C. 60% D. 10% E. No Change