Question

If the two lines of regression are $4x + 3y + 7 = 0$ and $3x + 4y + 8 = 0$, then the means of x and y are

• A. $- \frac{4}{7}, - \frac{11}{7}$
• B. $- \frac{4}{7},\frac{11}{7}$
• C. $\frac{4}{7}, - \frac{11}{7}$
• D. 4, 7

Answer 1

Answer: (A)

$- \frac{4}{7}, - \frac{11}{7}$

Answer 2

Since lines of regression pass through$(\bar{x},\bar{y})$, hence the equation will be $4\bar{x} + 3\bar{y} + 7 = 0$,$3\bar{x} + 4\bar{y} + 8 = 0$

On solving the above equations, we get the required answer $\bar{x} = - \frac{4}{7}$ and $\bar{y} = - \frac{11}{7}$.