A list of 13 numbers has an average of 339. When two numbers are deleted from the list, the average of the remaining numbers is 324.
- What is the sum of 13 numbers?
- What is the bigger number between the two numbers that have been deleted given that the difference between the two numbers is 3?
(a)
Sum of the 13 numbers
= 13 x 339
= 4407
(b)
Remaining numbers
= 13 - 2
= 11
Sum of the remaining numbers
= 324 x 11
= 3564
Sum of the two numbers
= 4407 - 3564
= 843
Smaller number = 1 u
Bigger number = 1 u + 3
Total = 1 u + 1 u + 3 = 2 u + 3
2 u + 3 = 843
2 u = 843 - 3
2 u = 840
1 u = 840 ÷ 2 = 420
Bigger number
= 1 u + 3
= 420 + 3
= 423
Answer(s): (a) 4407; (b) 423