Question 1161598
z=(x-mean).sd or (6000-5274)/600=1.21
probability z>1.21 is 0.1131
middle 50% occurs when z=-0.6745 to z=+0.6745 (25th and 75th percentiles
z*sd=+/- 404.69.  Add to and subtract that from the mean to get the limits
($4869.31, $5678.69)

Check on a TI-83 by 2ndVARS 2 ENTER(4869.31,5678.69,5274,600) ENTER That gives you the probability of that interval.