Angela is conducting a poll on campus to determine the next student representative. How many students does she need to sample for a confidence level of 90% with a margin of error of + or - 5%?

2 answers

degree of freedom for a chi-test depends on the sample size true or false
To Ana:

Try this formula:
n = [(z-value)^2 * p * q]/E^2

Note: n = sample size needed; .5 for p and .5 for q are used if no value is stated in the problem. E = maximum error, which is .05 (5%) in the problem. Z-value is found using a z-table (for 90%, the value is 1.645).
Note also that ^2 means squared and * means to multiply.

I'll let you take it from here. Be sure to round the value to the next highest whole number.

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To Anonymous:

Degrees of freedom for a chi-square test depends on the number of rows and columns.