If the foot length of women follows a normal distribution with a mean of 23 cm, and
81.5% have a foot length between 20 cm and 29 cm, what is your estimate of the standard
deviation of the heights in this population?

1) you deposit $2,500 in an account that earns 4% simple interest. how much do you earn in eight years?

Scores on a university exam are normally distributed with a mean of 78 and a standard deviation of 8. the professor teaching the class declares that a score of 70 or higher is required for a grade of at least “c.” using the 68-95-99.7 rule, what percentage of students failed to earn a grade of at least “c”?

If p(a) = 0.70 and p(b) = 0.20, then a and b are independent events if