A random sample of 64 students has a mean study time of 12 hours per week. The population standard deviation is known to be 4 hours. Construct a 95% confidence interval for the population mean using z* = 1.96.

Step 1: Identify the given values.

Sample mean:
x̄ = 12

Population standard deviation:
σ = 4

Sample size:
n = 64

For a 95% confidence interval:
z* = 1.96

Step 2: Calculate the standard error.

SE = σ / √n

SE = 4 / √64
SE = 4 / 8
SE = 0.5

Step 3: Calculate the margin of error.

Margin of error = z* × SE

ME = 1.96(0.5)
ME = 0.98

Step 4: Construct the confidence interval.

Lower endpoint:
12 - 0.98 = 11.02

Upper endpoint:
12 + 0.98 = 12.98

Step 5: Interpret the interval.

The 95% confidence interval for the population mean study time is from 11.02 to 12.98 hours per week.

Therefore, the confidence interval is (11.02, 12.98).