Answer:

Step-by-step explanation:
Since the sample size is quite large, we can use the z-distribution.
The margin of error is given by

Where n is the sample size, s is the sample standard deviation and
is the z-score corresponding to a 90% confidence level.
The z-score corresponding to a 90% confidence level is
Significance level = α = 1 - 0.90= 0.10/2 = 0.05
From the z-table at α = 0.05
z-score = 1.645

Therefore, the margin of error is 0.776.
If you simplify it, it would be that same as 2/3.
You have to ask yourself how would you read that decimal? It is 162 ten-thousandths because the last digit, which is 2 is in the ten-thousandths place. So the fraction would be 162/10000