Why is it important to avoid smaller sample size

The train station clock runs too fast and gains 5 minutes every 10 days. how many minutes and seconds will it have gained at the end of 9 days?

You eat $0.85 for every cup of hot chocolate you sell. how many cups do you need to sell to earn $55.25

Gia opened two savings accounts at two different banks. one account earns an annual 3.4% simple interest, and the other earns half as much. if she deposited $500 in each account, how much total interest will she have earned in 5 years? a. $34.00 b. $25.50 c. $51.00 d. $510.00