A list of 12 numbers has an average of 347. When two numbers are deleted from the list, the average of the remaining numbers is 309.
- What is the sum of 12 numbers?
- What is the bigger number between the two numbers that have been deleted given that the difference between the two numbers is 2?
(a)
Sum of the 12 numbers
= 12 x 347
= 4164
(b)
Remaining numbers
= 12 - 2
= 10
Sum of the remaining numbers
= 309 x 10
= 3090
Sum of the two numbers
= 4164 - 3090
= 1074
Smaller number = 1 u
Bigger number = 1 u + 2
Total = 1 u + 1 u + 2 = 2 u + 2
2 u + 2 = 1074
2 u = 1074 - 2
2 u = 1072
1 u = 1072 ÷ 2 = 536
Bigger number
= 1 u + 2
= 536 + 2
= 538
Answer(s): (a) 4164; (b) 538