Suppose that two groups are being compared one with a sample

Suppose that two groups are being compared, one with a sample size, n = 10, and the other with a sample size, n = 15. The standard deviation of the measurements within the first group is 1.5, and the standard deviation of the measurements within the second group is 2.5. The sample mean within the first group is 10 and the sample mean within the second group is 15. Find the standard error of top enclose y subscript 1 minus top enclose y subscript 2

Solution

standard error of means = sqrt[ s1^2/n1 + s2^2/n2]

= sqrt[1.5^2/10 + 2.5^2/15]

= 0.801