Question

the average age of 5 student is 15 years the sum their ages is​

Answer 1

Answer:

Average age = sum of age of all students/ total no. Of Student

Hence, 15 = sum of age of all ten students/10

=> Sum of age of all students = 15* 10= 150

Acc to ques. Now total students = 10+5= 15

Average age = 16

Again, average age = sum of age / total no. Of students

16 = sum of ages of fifteen students/ 15

Sum of age of 15 students = 16*15 =240

Hence sum of age of 5 new students = 240 - 150 = 90

Thus average age of 5 new students = 90/5= 14

Answer 2

Answer:

Average age = 15 years

Number of students = 5

Average age = Sum of ages/ Number of students

Sum of ages = Average age × Number of students

Sum of their ages = 15×5 years = 75 years

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