ASSUME THE THE MEAN WEIGHT OF CHILDREN AGES 7 IS 50 POUNDS AND A STANDARD DEVIATION OF 10. wHAT IS THE PROBABLITY THAT A RANDOM SELECTED 7 YEAR OLD WILL HAVE A WEIGHT THAT IS LESS THAT 65
STATISTICS - JJ, Monday, February 11, 2013 at 6:45pm
You have to find the z-score.
65-50 = 15 then divide by 10 which is z = 1.5
You can then use a z-table or a stat calculator to find the probablity less than 65%
Depending on the table, you may want to find the probability of z = 1.5 or greater and then subtract that number from 1 to get the less than.
STATISTICS - Kamryn, Friday, June 6, 2014 at 8:47am
For a normal distribution, what is the probability of randomly selecting a z score greater than Z=- 2.0