Let a sample have the following characteristics :
- Standard deviation : \sigma=4
- Mean : \bar{x}=36
We need to have a 95% probability for the population mean to be between 34 and 38.
What is the minimum value of n ?
We weigh a sample of apples of a garden. The mean of the weight of these gardens is 86 grams and the standard deviation is 6.2 grams. We need to have a 95% probability for the mean to be between 84 and 88.
What is the minimum value of n ?
We choose a sample of bottled water to determine the pH (the acidity scale) of the water produced by a company. The mean of the pH of the sample is 6.52 and the standard deviation is 0.11.
What is the minimum value of n to have a 99% probability for the population mean to be between 6.50 and 6.54 ?
We measure the height of a sample of people. The mean of the sample is 175 cm and the standard deviation is 20 cm.
What is the minimum value of n to have a 95% probability for the population mean to be between 170 and 180 ?
We choose a sample of the grades of n students in a math class. The mean of the grades is 14 and the standard deviation is 4.
What is the minimum value of n to have a 90% probability for the mean to be between 12.5 and 15.5 ?
We choose a sample n bottles of juice. The mean of the volume of sample is 997 ml and the standard deviation is 15 ml.
What is the minimum value of n to have a 99% probability for the population mean to be between 990 ml and 1\ 004. ml?
A medical center chooses a sample of n clients who regularly smoke. Assume that the mean of the ages of the clients is 43 and the standard deviation is 12.
What is the minimum value of n to have a 90% probability for the population mean to be between 37 and 49.