A list of 18 numbers has an average of 332. When two numbers are deleted from the list, the average of the remaining numbers is 325.
- What is the sum of 18 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 18 numbers
= 18 x 332
= 5976
(b)
Remaining numbers
= 18 - 2
= 16
Sum of the remaining numbers
= 325 x 16
= 5200
Sum of the two numbers
= 5976 - 5200
= 776
Smaller number = 1 u
Bigger number = 1 u + 4
Total = 1 u + 1 u + 4 = 2 u + 4
2 u + 4 = 776
2 u = 776 - 4
2 u = 772
1 u = 772 ÷ 2 = 386
Bigger number
= 1 u + 4
= 386 + 4
= 390
Answer(s): (a) 5976; (b) 390