The average of 11 results is 50. If the average of the first six results is 49 and that of the last six is 52, the sixth no. is

According to question average of 11 number is = 50

Sum of 11 numbers is = 50 × 11 = 550

$\Rightarrow 49\times 6=294$

$\Rightarrow 52\times 6=312$

  6th number  $=312+294-550=56$.