Suppose the wait to pass through immigration at JFK Airport in New York is thought to be bell-shaped and symmetrical with a mean of 22 minutes. It is known that 68% of travelers will spend between 16 and 28 minutes waiting to pass through immigration. The standard deviation for the wait time through immigration is ________.
A) 6 minutes
B) 8 minutes
C) 9 minutes
D) 10 minutes

Question

Quizplus · Accepted Answer

The standard deviation is 6 minutes because in a bell-shaped, symmetrical distribution, 68% of the data falls within one standard deviation of the mean. Here, 22 minutes is the mean, and 16 to 28 minutes represents this range, which is 6 minutes away from the mean on either side.

Suppose the Wait to Pass Through Immigration at JFK Airport