Answer:
The standard error between the sample mean is approximately 0.3412
Explanation:
The equation for the standard error of a difference in sample mean of equal sample sizes is given as follows;
The given parameters are;
The number of sample of southern grass cicadas, n₁ = 20
The mean body length of the southern grass cicadas,
= 16.22 mm
The standard deviation, s₁ = 1.34 mm
The number of sample of citrus cicadas, n₂ = 20
The mean body length of the citrus cicadas,
= 13.41 mm
The standard deviation, s₂ = 0.73 mm
The standard error between the sample mean, SE ≈ 0.3412