Let X¯ be the mean of x1,x2,...,xn, and Y¯ the mean of y1,y2,...,yn, if Z¯ is the mean of x1,x2,...,xn, y1,y2,...,yn, then Z¯ is equal to (a) X¯ +Y¯(b) X¯+Y¯2(c) X¯+Y¯n(d) X¯+Y¯2n

Let X¯ be the mean of x1,x2,...,xn, and Y¯ the mean of y1,y2,...,yn

1.	Let X¯ be the mean of x1,x2,...,xn, and Y¯ the mean of y1,y2,...,yn, if Z¯ is the mean of x1,x2,...,xn, y1,y2,...,yn, then Z¯ is equal to (a) X¯ +Y¯(b) X¯+Y¯2(c) X¯+Y¯n(d) X¯+Y¯2n
Answer» Let $\bar{X}$ be the mean of x₁,x₂,...,x_n, and $\bar{Y}$ the mean of y₁,y₂,...,y_n, if $\bar{Z}$ is the mean of x₁,x₂,...,x_n, y₁,y₂,...,y_n, then $\bar{Z}$ is equal to $(a) \bar{X} + \bar{Y} (b) \frac{\bar{X} + \bar{Y}}{2} (c) \frac{\bar{X} + \bar{Y}}{n} (d) \frac{\bar{X} + \bar{Y}}{2 n}$