A list of 18 numbers has an average of 345. When two numbers are deleted from the list, the average of the remaining numbers is 322.
- What is the sum of 18 numbers?
- What is the bigger number between the two numbers that have been deleted given that the difference between the two numbers is 6?
(a)
Sum of the 18 numbers
= 18 x 345
= 6210
(b)
Remaining numbers
= 18 - 2
= 16
Sum of the remaining numbers
= 322 x 16
= 5152
Sum of the two numbers
= 6210 - 5152
= 1058
Smaller number = 1 u
Bigger number = 1 u + 6
Total = 1 u + 1 u + 6 = 2 u + 6
2 u + 6 = 1058
2 u = 1058 - 6
2 u = 1052
1 u = 1052 ÷ 2 = 526
Bigger number
= 1 u + 6
= 526 + 6
= 532
Answer(s): (a) 6210; (b) 532