The daily amount of water consumed by twenty year olds is known to be normally distributed with mean 1.4 liters and standard deviation 0.6 liters.

(a) What is the probability that the mean amount of water consumed per day by 8 randomly selected twenty year olds is between 1.2 and 1.5 liters?

(b) If I randomly select 7 twenty year olds, what is the probability that none of them drink more than 2.6 liters of water per day?

I find that P[1.2

Question

The daily amount of water consumed by twenty year olds is known to be normally distributed with mean 1.4 liters and standard deviation 0.6 liters.

(a) What is the probability that the mean amount of water consumed per day by 8 randomly selected twenty year olds is between 1.2 and 1.5 liters?

(b) If I randomly select 7 twenty year olds, what is the probability that none of them drink more than 2.6 liters of water per day?


I find that P[1.2 < X < 1.5] = 0.19674 assuming one person but the rest I don't understand how to solve...