If the estimated population standard deviation based on previous studies is 20 percent, the acceptable error is plus or minus 5 percent, and the z-value for a 95 percent level of confidence is 1.96, the needed sample size is approximately:

The needed sample size is approximately 61.46 individuals.

Step-by-step explanation:

We can use the following formula to obtain the sample size:

Where is the standard deviation, is the quantile of the normal distribution with area of and is the acceptable error.

We would need a sample size of 62 individuals.

in if you ask questions, the points are taken from your total and given to the one who answered it..

so if i have 30 points and i ask a question for 5 points, then when someone asks a question i will lose 5 points and the answerer earns 5

happy to