The average of seven numbers is 18. If one of the number is 17 and if it is replaced by 31, then the average becomes: 

The average of four consecutive even numbers is 15. The 2nd highest number is: 

Eight consecutive numbers are given. If the average of the two numbers that appear in the middle is 6, then the sum of the eight given numbers is: 

The average weight of a group of 20 boys was calculated to be 89.4 kg and it was later discovered that one weight was misread as 78 kg instead of 87 kg. The correct average weight is 

Among three numbers, the first is twice the second and thrice the third. If the average of the three numbers is 49.5, then the difference between the first and the third number is: 

The average weight of P, Q and R is 93 kg. If the average weight of P and Q is 89 kg and that of Q and R average weight is 96.5 kg ,  then the weight (in kg) of Q is____.

a, b, c, d, e, f, g are consecutive even numbers. j, k, l, m, n are consecutive odd numbers. The average of all the numbers is: 

The average of three consecutive odd numbers is 12 more than one third of the first of these numbers. What is the last of the three numbers?