+491 The weights of grapefruits in a bin are normally distributed with a mean of 261 grams and a standard deviation of 9.4 grams.
Approximately 20% of the grape fruits weight less than which amount?
239
247
253
261
+37146 You need to find the z-score which is closest to .2000 (20%)
Look at your negative z-score table
Look at z= -.84
So -.84 standard deviations below the mean represents 20% 261 - .84 X (9.4) = 253.1 gms
