Answer:
a. 
b. 
Step-by-step explanation:
a. 
A mixed fraction of the form 



b. 
A mixed fraction of the form 




Hence, the answer.
Step-by-step explanation:
We know that,

Where,
X = raw score = 84
μ = mean = 68
σ = standard deviation = 10
Putting the values,

The percent of his sales that were less than or equal to 84 inches, is

Therefore, the remaining 100-94.5=5.5% were more than 84 inches.