Question
Download Solution PDFAverage age of a Group of 40 boys is 15 years. A boy of age 20 years leaves the group and a new boy joins the group. If the average age of the new group becomes 15.2 years, then find the age of the new boy.
Answer (Detailed Solution Below)
Detailed Solution
Download Solution PDFThe total age of the group = 40 × 15 = 600 years.
When a 20-year-old boy leaves the group, the total age becomes
600 - 20 = 580 years.
Now, a new boy joins the group and the average age of the group
becomes 15.2 years.
The total age of the new group is 15.2 × 40 = 608 years.
The difference between the total age of the new group and the total
age after the 20-year-old boy left is the age of the new boy: 608 -
580 = 28 years.
So, the new boy is 28 years old.
Therefore, the answer is 28 years.
Last updated on Jun 22, 2025
-> The UGC Net Admit Card has been released on its official website today.
-> The UGC NET June 2025 exam will be conducted from 25th to 29th June 2025.
-> The UGC-NET exam takes place for 85 subjects, to determine the eligibility for 'Junior Research Fellowship’ and ‘Assistant Professor’ posts, as well as for PhD. admissions.
-> The exam is conducted bi-annually - in June and December cycles.
-> The exam comprises two papers - Paper I and Paper II. Paper I consists of 50 questions and Paper II consists of 100 questions.
-> The candidates who are preparing for the exam can check the UGC NET Previous Year Papers and UGC NET Test Series to boost their preparations.