A list of 13 numbers has an average of 350. When two numbers are deleted from the list, the average of the remaining numbers is 321.
- 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 350
= 4550
(b)
Remaining numbers
= 13 - 2
= 11
Sum of the remaining numbers
= 321 x 11
= 3531
Sum of the two numbers
= 4550 - 3531
= 1019
Smaller number = 1 u
Bigger number = 1 u + 3
Total = 1 u + 1 u + 3 = 2 u + 3
2 u + 3 = 1019
2 u = 1019 - 3
2 u = 1016
1 u = 1016 ÷ 2 = 508
Bigger number
= 1 u + 3
= 508 + 3
= 511
Answer(s): (a) 4550; (b) 511