Quiz 06 Normal Curves 7.1 • Name:

1. For the following curves A, B, and C determine the mean and the standard deviation σ:
normalcurvesthree (10K)
normal (3K)

CurveMean standard deviation σ
A  
B  
C  

2. Green coffee beans roasted with a hot air popper are properly roasted at "second crack." On average, the beans reach second crack at a mean of six minutes with a standard deviation of one minute. Assume that the roasting distribution for the beans is normal and that there are fifty beans in the hot air popper.

  1. __________ What is the probability a bean will be properly roasted after eight minutes?
  2. __________ How many beans will reach second crack between four and five minutes?
  3. __________ If I want to wait until 84.13% of the beans are roasted, how many minutes do I have to wait?