|
Averages
December 22, 2003
The average age of a group of 10 students was 20. The average age increased by 2 years when two new students joined the group. What is the average age of the two new students who joined the group?
| (1) | 22 years |
| (2) | 30 years |
| (3) | 44 years |
| (4) | 32 years |
| (5) | None of these |
Correct Answer Choice (4)
Solution:
The average age of a group of 10 students is 20.
Therefore, the sum of the ages of all 10 of them = 10 * 20 = 200
When two new students join the group, the average age increases by 2. New average = 22
Now, there are 12 students.
Therefore, the sum of the ages of all 12 of them = 12 * 22 = 264
Therefore, the sum of the ages of the two new students who joined = 264 – 200 = 64
And the average age of each of the two new students = 64/2 = 32 years.
| 
