Question : The average age of 30 students in a class is 14 years, 4 months. After the admission of five new students in the class, the average becomes 13 years and 9 months. The youngest of the five new students is 9 years and 11 months old. The average age of the remaining four new students is:
Option 1: 11 years 2 months
Option 2: 13 years 6 months
Option 3: 12 years 4 months
Option 4: 10 years 4 months
Latest: SSC CGL preparation tips to crack the exam
Don't Miss: SSC CGL complete guide
New: Unlock 10% OFF on PTE Academic. Use Code: 'C360SPL10'
Correct Answer: 10 years 4 months
Solution : Using Average = $\frac{\text{Sum of all observations}}{\text{Number of observations}}$ Sum of the ages of 30 students = 30 × 14$\frac{4}{12}$ = 30 ×14$\frac{1}{3}$ = 30 × $\frac{43}{3}$ = 430 years Sum of age of 35 students after admission = 35 × 13$\frac{9}{12}$ = 35 ×13$\frac{3}{4}$ = 35 × $\frac{55}{4}$ = $\frac{1925}{4}$ years Total age of 5 students = 35 students – 30 students = $\frac{1925}{4}$ – 430 = $\frac{1925-1720}{4}$ = $\frac{205}{4}$ = $51\frac{1}{4}$ years i.e., 51 years 3 months Given: Age of one student = 9 years 11 months Sum of age of 4 students = 51 years 3 months – 9 years 11 months = 41 years 4 months So, the average age of the remaining 4 students = $\frac{\text{41 years 4 months}}{4}$ (Converting years in months we get 496 months) = $\frac{496}{4}$ = 10 years 4 months Hence, the correct answer is '10 years 4 months'.
Candidates can download this ebook to know all about SSC CGL.
Answer Key | Eligibility | Application | Selection Process | Preparation Tips | Result | Admit Card
Question : The average age of 7 students in a class is 28 years. The average age of the first three students is 30 years. The age of the fourth student is 4 years less than the age of the fifth student. The ages of the last two students are the same and are 5 more than the average age of
Question : In a school with 600 students, the average age of the boys is 12 years and that of the girls is 11 years. If the average age of the school is 11 years and 9 months, then the number of girls in the school is:
Question : The ratio between the present ages of A and B is 3 : 5. If the ratio of their ages five years hence becomes 13 : 20, then the present age of B is:
Question : In 6 minutes, $\frac{4}{13}$ of a bucket is filled. How much time will it take to fill the remaining bucket?
Question : After replacing an old member with a new member. It was found that the average age of five members of a club is the same as it was three years ago. The difference between the ages of the replaced and the new members is:
Regular exam updates, QnA, Predictors, College Applications & E-books now on your Mobile