+0  
 
0
4766
3
avatar

Assume that the weight loss for the first month of a diet program varies between 6 pounds and 12 pounds, and is spread evenly over the range of possibilities, so that there is a uniform distribution. Find the probability of the given range of pounds lost. Between 8 pounds and 11 pounds

 Mar 16, 2016

Best Answer 

 #3
avatar+124 
+5

Thanks for that addition Geno. That was a possiblity I did not consider. smileysmileysmiley

 Mar 17, 2016
 #1
avatar+124 
+5

Well to make it as simple as possible we'll assume that distribution is one pound. So out values are 6, 7, 8, 9, 10, 11 and 12. A total of 7 possible amounts. Out of those 7, 4 of them are between 8 and 11(8, 9, 10 and 11). Therefore the probability of losing between 8 and 11 points is 4/7. This would change if your distribution was say 2 pounds, or half a pound.

 Mar 16, 2016
 #2
avatar+23252 
+5

Adonai is absolutely correct if you have a discrete distribution with weight losses of either 6 or 7 or 8 or ... 12 pounds.

He also correctly states that you need to alter your answer if the losses have a step of 2 pounds each, such as either 6 or 8 or 10 or 12, or 1/2 pound each, such as either 6 or 6 1/2 or 7 1/2 or ... or 12 pounds. And you solve these cases in exactly the way that he solved it for a step of 1 pound.

However, if you have a continuouts distribution, one that allows every possible loss (using every possible fraction) between 6 and 12 pounds, then find the distance between 6 and 12 pounds (12 - 6 = 6) and find the distance between 8 and 11 (11 - 8  =  3), then divide this sub-distance by the total distance:  3 / 6  =  1/2   =  0.50, giving a probability of 0.50.

 Mar 17, 2016
 #3
avatar+124 
+5
Best Answer

Thanks for that addition Geno. That was a possiblity I did not consider. smileysmileysmiley

Adonai Mar 17, 2016

0 Online Users