A list of 15 numbers has an average of 341. When two numbers are deleted from the list, the average of the remaining numbers is 314.
- What is the sum of 15 numbers?
- What is the bigger number between the two numbers that have been deleted given that the difference between the two numbers is 1?
(a)
Sum of the 15 numbers
= 15 x 341
= 5115
(b)
Remaining numbers
= 15 - 2
= 13
Sum of the remaining numbers
= 314 x 13
= 4082
Sum of the two numbers
= 5115 - 4082
= 1033
Smaller number = 1 u
Bigger number = 1 u + 1
Total = 1 u + 1 u + 1 = 2 u + 1
2 u + 1 = 1033
2 u = 1033 - 1
2 u = 1032
1 u = 1032 ÷ 2 = 516
Bigger number
= 1 u + 1
= 516 + 1
= 517
Answer(s): (a) 5115; (b) 517