Let X1, X2, . . . , X5 be a random sample of SAT mathematics scores, assumed to be N(X, 2), and let Y1, Y2,

Let X1, X2, . . . , X5 be a random sample of SAT mathematics scores, assumed to be N(μX, σ2), and let Y1, Y2, . . . , Y8 be an independent random sample of SAT verbal scores, assumed to be N(μY, σ2). If the following data are observed, find a 90% confidence interval for μX ˆ’ μY:

x1=644 x2 = 493 x3=532 x4=462 x5=565