A list of 15 numbers has an average of 350. When two numbers are deleted from the list, the average of the remaining numbers is 302.
- 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 4?
(a)
Sum of the 15 numbers
= 15 x 350
= 5250
(b)
Remaining numbers
= 15 - 2
= 13
Sum of the remaining numbers
= 302 x 13
= 3926
Sum of the two numbers
= 5250 - 3926
= 1324
Smaller number = 1 u
Bigger number = 1 u + 4
Total = 1 u + 1 u + 4 = 2 u + 4
2 u + 4 = 1324
2 u = 1324 - 4
2 u = 1320
1 u = 1320 ÷ 2 = 660
Bigger number
= 1 u + 4
= 660 + 4
= 664
Answer(s): (a) 5250; (b) 664