A list of 15 numbers has an average of 349. When two numbers are deleted from the list, the average of the remaining numbers is 319.
- 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 2?
(a)
Sum of the 15 numbers
= 15 x 349
= 5235
(b)
Remaining numbers
= 15 - 2
= 13
Sum of the remaining numbers
= 319 x 13
= 4147
Sum of the two numbers
= 5235 - 4147
= 1088
Smaller number = 1 u
Bigger number = 1 u + 2
Total = 1 u + 1 u + 2 = 2 u + 2
2 u + 2 = 1088
2 u = 1088 - 2
2 u = 1086
1 u = 1086 ÷ 2 = 543
Bigger number
= 1 u + 2
= 543 + 2
= 545
Answer(s): (a) 5235; (b) 545