Question

In: Electrical Engineering

If you wish to estimate the proportion of engineers who have studied probability theory and you...

If you wish to estimate the proportion of engineers who have studied probability theory and you
wish your estimation to be correct within 2% with probability 95% or more, how large the sample
you would take
(a) if you have no idea what the true proportion is, [Ans: 12500]
(b) if you are confident that the true proportion is less than 0.2. [Ans: 8000]

Solutions

Expert Solution

ANSWER ::

A true proportion is an equation that states that two ratios are equal. If you know one ratio in a proportion, you can use that information to find values in the other equivalent ratio.

In 2016, the latest year for which Occupational Employment Statistics survey data are available, 6.9 million people were employed in the United States as scientists and engineers, accounting for 4.9% of total U.S. employment.

Given that

=2 %=2/100=0.02

probability p=95%=95/100=0.95


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