The average age of a group of 25 girls is 10year. If one girl, aged 12 years and 4 months joins the group, find the new average age of the group
Answer Details
To find the new average age of the group, we need to calculate the sum of the ages of all the girls in the group after the new girl joins, and then divide by the total number of girls in the group.
The sum of the ages of the original 25 girls is 25 * 10 = 250 years.
When the new girl joins the group, the total number of girls becomes 26, and the sum of their ages becomes 250 + 12.33 (12 years and 4 months converted to decimal form) = 262.33 years.
To find the new average age, we divide the sum of the ages by the number of girls:
New average age = 262.33 / 26 ≈ 10.1 years
Therefore, the new average age of the group is 10.1 years.