Adult panda weights are normally distributed with a mean of 200 pounds and a standard distribution of 20 pounds. The largest pandas weigh over 250 pounds. Approximately what percent of the adult pandas weight over 250 pounds?
To answer this problem we have to have a Standard Normal Distribution table because we need to look up z scores. Then we use this equation
z = (value - mean)/(standard deviation) = (250-200)/20 = 2.5.
The z score is then 2.5 If so, look up z=2.5 on the left edge then you then determine from the table what the area to the left of that is.
Here are the conditions:
p(z>2.5)=1
p(z<2.5)=.621
1-.621= .379
100-37.9= 62.1
Given that, we should go with .621%.
250-200/20=2.5
P(2.5)=.9938
that's the probability under 250 pounds. over would be 1-.9938=.0062
0.62%