MM plain candies have a mean weight of 08565 g and a standar
M&M plain candies have a mean weight of 0.8565 g and a standard deviation of 0.0518g. The M&M candies used in Data Set 20 came from a package containing 465 candies, and the package label stated that the net weight is 396.9g
 1. If on M&M plain candy is randomly seleced, find the probability that it weighs between 0.8535g and 0.8565g
 2. If one M&M plain candy is randomly selected, find the probability that it weighs more than 0.8535g
 3. If package (Containing 465 M&M candies) is randomly selected, find the probability its mean weight is between 0.8535g and 0.8565g
 4. If 465 M&M plain candies are randomly selected, find the probability their mean weight is at least 0.8535g?
 5. Does it seem that the Mars cpompany is providing M&M consumers with the amount claimed on the label? (If every package has 465 candies, the mean weight of the candies must exceed 396.9/465 = 08535g for the net contents to weigh atleast 396.9g)
 
 (Answer with explanation please)
Solution
1.
We first get the z score for the two values. As z = (x - u) / s, then as          
 x1 = lower bound =    0.8535      
 x2 = upper bound =    0.8565      
 u = mean =    0.8565      
           
 s = standard deviation =    0.0518      
           
 Thus, the two z scores are          
           
 z1 = lower z score = (x1 - u)/s =    -0.057915058      
 z2 = upper z score = (x2 - u) / s =    0      
           
 Using table/technology, the left tailed areas between these z scores is          
           
 P(z < z1) =    0.476908144      
 P(z < z2) =    0.5      
           
 Thus, the area between them, by subtracting these areas, is          
           
 P(z1 < z < z2) =    0.023091856   [ANSWER]
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2.
We first get the z score for the critical value. As z = (x - u) / s, then as          
           
 x = critical value =    0.8535      
 u = mean =    0.8565      
           
 s = standard deviation =    0.0518      
           
 Thus,          
           
 z = (x - u) / s =    -0.057915058      
           
 Thus, using a table/technology, the right tailed area of this is          
           
 P(z >   -0.057915058   ) =    0.523091856 [ANSWER]
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3.
We first get the z score for the two values. As z = (x - u) sqrt(n) / s, then as          
 x1 = lower bound =    0.8535      
 x2 = upper bound =    0.8565      
 u = mean =    0.8565      
 n = sample size =    465      
 s = standard deviation =    0.0518      
           
 Thus, the two z scores are          
           
 z1 = lower z score = (x1 - u) * sqrt(n) / s =    -1.248872123      
 z2 = upper z score = (x2 - u) * sqrt(n) / s =    0      
           
 Using table/technology, the left tailed areas between these z scores is          
           
 P(z < z1) =    0.105855925      
 P(z < z2) =    0.5      
           
 Thus, the area between them, by subtracting these areas, is          
           
 P(z1 < z < z2) =    0.394144075   [ANSWER]
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4.
We first get the z score for the critical value. As z = (x - u) sqrt(n) / s, then as          
           
 x = critical value =    0.8535      
 u = mean =    0.8565      
 n = sample size =    465      
 s = standard deviation =    0.0518      
           
 Thus,          
           
 z = (x - u) * sqrt(n) / s =    -1.248872123      
           
 Thus, using a table/technology, the right tailed area of this is          
           
 P(z >   -1.248872123   ) =    0.894144075 [ANSWER]
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5.
It seems so, because part 4 is really a high probability. [ANSWER]
   


