Final answer:
To estimate the probability that a household personal computer is used for entertainment between 1.8 and 2.75 hours per day, we can use the assumption of a symmetric and bell-shaped probability density curve to estimate the probability within 1 standard deviation of the mean as approximately 68%. Therefore, the estimated probability is around 34%.
Step-by-step explanation:
To find the probability that a household personal computer is used for entertainment between 1.8 and 2.75 hours per day, we need to determine the area under the probability density curve for that range of values.
Given that we do not have the specific probability density curve or its function, we cannot calculate the exact probability. However, if we assume that the probability density function is approximately symmetric and bell-shaped, we can estimate the probability within the range.
For a symmetric and bell-shaped probability density curve, the probability within 1 standard deviation of the mean is approximately 68%. Therefore, we can estimate the probability of a household personal computer being used for entertainment between 1.8 and 2.75 hours per day to be around 34%.