Answer:
Answer to Suppose that IQ scores have a bell-shaped distribution with a mean of ... Question: Suppose That IQ Scores Have A Bell-shaped Distribution With A Mean Of 105 And A Standard Deviation Of 15. ... Please Do Not Round Your Answer. ... Using the empirical rule, what percentage of IQ scores are greater than 120?Step-by-step explanation:
Divide them and then multiply
Answer:
Step-by-step explanation:
In the past, mean of age of employees
i.e. 
Recently sample was taken
n = sample size = 60
Mean of sample = 45
Std dev of sample s = 16

(Right tailed test)
Since only population std deviation is known we can use t test only
Std error = 
Mean difference = 45-40 =5
Test statistic t=
df = 60
p value =0.008739
Since p < 0.05 we reject null hypothesis
The mean age has increased.
Answer:
32
Step-by-step explanation: