Management Aptitude Test 2018 Paper

(b) Let the 11 consecutive odd numbers be y, y + 2, y + 4 , ........... Sum of 7 consecutive odd numbers
= $\frac{7}{2}$ [2y + 6 x 2] = $\frac{7}{2}$ (2y + 12)
= 7(y + 6) [ ∵ sum of an AP = $\frac{\mathit{n}}{2}$ [2a + (n - 1) d]
Hence, Average of 7 consecutive numbers = $\frac{7\left(\mathit{y}+6\right)}{7}$ = Y + 6
And, y + 6 = x (given)
⇒y = x - 6
Again, Average of 11 consecutive numbers
= $\frac{\frac{11}{2}\left[2\mathit{y}+\left(11-1\right)2\right]}{11}$ = $\frac{1}{2}$[2y + 20] = y + 10
= x - 6 + 10 [∵ y = x - 6]= x + 4