A list of 18 numbers has an average of 345. When two numbers are deleted from the list, the average of the remaining numbers is 304.
- 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 6?
(a)
Sum of the 18 numbers
= 18 x 345
= 6210
(b)
Remaining numbers
= 18 - 2
= 16
Sum of the remaining numbers
= 304 x 16
= 4864
Sum of the two numbers
= 6210 - 4864
= 1346
Smaller number = 1 u
Bigger number = 1 u + 6
Total = 1 u + 1 u + 6 = 2 u + 6
2 u + 6 = 1346
2 u = 1346 - 6
2 u = 1340
1 u = 1340 ÷ 2 = 670
Bigger number
= 1 u + 6
= 670 + 6
= 676
Answer(s): (a) 6210; (b) 676