This study serves as a teaching aid for teachers of introductory statistics. The aim of this study was limited to determining various sample sizes when estimating population proportion. Tables on sample sizes were generated using a C[superscript ++] program, which depends on population size, degree of precision or error level, and confidence level. Nineteen different population sizes, five degrees of precision, and three levels of confidence were utilized. The study found that the larger the population size, the higher the degree of precision, and the higher the probability/confidence level, the larger the sample size must be. Two values for the sample estimate of the population proportion were used in this study. Practical applications of randomly pulling appropriate number of samples from huge data sets were also discussed. (Contains 6 tables.)