Question
How is the optimal sample size determined in statistical
analysis?Solution
The optimal sample size is determined using statistical formulas that balance the desired margin of error (the degree to which the sample's estimate can differ from the true population value) and the confidence level (the likelihood that the sample's results reflect the population's characteristics). These calculations ensure that the sample size is large enough to be statistically significant, but not unnecessarily large, which could waste resources. Factors such as the population size, variability within the population, and the desired precision of the results all play a role in determining the sample size. Why Other Options Are Incorrect: • A: Convenience-based sampling can introduce bias and does not ensure a representative sample. • C: Trial and error is an inefficient approach and does not guarantee statistical significance. • D: Collecting an unnecessarily large sample may increase costs and time without improving accuracy. • E: A fixed percentage of the population is not an appropriate method for determining sample size. The size must be calculated based on statistical principles.
A shopkeeper buys 20 articles for Rs 5,000. He sells each article at 25% profit on the cost price. Due to a seasonal sale, he offers a 10% discount on t...
A shopkeeper sold three types of items A, B and C. He sold items A and B in the ratio of 16:21, while sold items C and A in the ratio of  5:8. The pri...
A person buys books at Rs. 300 for 5 and sells them at Rs.740. How many books must he sell in order to earn profit of Rs. 3,520?
The marked price of an article is Rs. 3260. The shopkeeper offered a 15% discount on it and made a profit of 10.84%. What is the percentage by which th...
Three partners ‘A’, ‘B’ and ‘C’ started a business by investing in the ratio 2:5:6 respectively and the ratio of time for which they made th...
Khushi’s earnings decreased by 45% and after that subsequently increased by 45%. Find the final loss % on his earnings.
A purchased an article for Rs 1560. She sold the article at 10% profit. She then added Rs 325 to the amount received and purchased a purse such t...
A dishonest shopkeeper makes a cheating of 25% at the time of buying the goods and 37.5% cheating at the time of selling the goods. He promises to sell ...
A dealer buys three types of mangoes at Rs. 40, Rs. 30 and Rs. 10 kg respectively. He mixes them in the ratio of 2:3:4 by weight and sells them at a pro...
Sara sold 30 scarves at a profit of 25%. If she had sold all the scarves for Rs. 3000 more, her overall profit would have been 50%. What is the selling ...