Question

Most married couples have two or three personality preferences in common. A random sample of 384 married couples found that 136 had three preferences in common. Another random sample of 588 couples showed that 214 had two personality preferences in common. Let p₁ be the population proportion of all married couples who have three personality preferences in common. Let p₂ be the population proportion of all married couples who have two personality preferences in common.

(a) Find a 95% confidence interval for p₁ – p₂. (Use 3 decimal places.)

lower limit
upper limit

Answer 1

Refer Standard normal table/Z-table or use excel function "=NORM.S.INV((1-0.025))" to find the critical value of z.