Slader the internal revenue service claims it takes an average of 3.7 hours to complete a 1040 tax form, assuming th4e time to c
1 answer:
Answer:
0.9953, 3.3629<x<4.0371
Step-by-step explanation:
Given that slader the internal revenue service claims it takes an average of 3.7 hours to complete a 1040 tax form, assuming th4e time to complete the form is normally distributed witha standard devait of the 30 minutes:
If X represents the time to complete then
X is N(3.7, 0.5) (we convert into uniform units in hours)
a) percent of people would you expect to complete the form in less than 5 hours
=
b) P(b<x<c) = 0.50
we find that here
c = 4.0371 and
b = 3.3629
Interval would be
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