Answer: 1416
============================================================
Step-by-step explanation:
Usually a 95% level is standard for many stats problems like this. Unfortunately a 94% confidence level is a bit unusual. But you can use an inverse z calculator to determine that the z critical value is approximately z = 1.881
The error we want is E = 0.025 or smaller.
We don't know the sample proportion phat, but we can make the conservative estimate of phat = 0.5
Plug these values into the min sample size formula below
This formula applies to proportions (instead of the mean).
n = phat*(1-phat)*(z/E)^2
n = 0.5*(1-0.5)*(1.881/0.025)^2
n = 1415.2644 approximately
n = 1416 is the final answer
Always round UP to the nearest whole number when it comes to min sample size problems like this.
Side note: if you used z = 1.88, then it would lead to n = 1414. So it depends on how accurate of a z value you use that determines the final answer. Luckily, 1414 is fairly close to 1416. I'd stick with 1416.