Final answer:
To find the sample mean, use the formula for the z-score and set up two equations to solve for the mean.
Step-by-step explanation:
To find the sample mean, we can use the formula for the z-score:
z = (x - μ) / σ
where z is the z-score, x is the value, μ is the mean, and σ is the standard deviation.
From the information given, we have:
z = -0.25 when x = sample mean - 3
z = -0.75 when x = 44
Plugging in these values, we can set up two equations to solve for the sample mean:
Equation 1: -0.25 = (sample mean - 3 - μ) / σ
Equation 2: -0.75 = (44 - μ) / σ
Solving these equations simultaneously will give us the sample mean.