The average age of 10 students and their teachers is 20 years.If the teacher's age is excluded , their average age reduces by 2 years.what is the teacher's age ?
Answers
Answer:
The teacher's age is 40 years.
Step-by-step explanation:
Let the average age of 10 students and their teacher be A = 20 years.
A = (sum of ages of students and their teacher)/(number of students+1)
20 = (sum of ages of students and their teacher)/11
Therefore the sum of ages of students and their teacher = 20 × 11 = 220
The average age when the age of the teacher is not there
= 20 -2 = 18
18 = sum of the ages of students / 10
The sum of the ages of students = 18 × 10 = 180
Teacher's age = (sum of ages of students and their teacher) - ( sum of ages of students )
= 220 -180 = 40
Therefore teacher's age = 40
Answer:
Teacher's age is 40 years.
Step-by-step explanation:
As per question
We have given ,
The average age of 10 students and their teachers = 20 years
teacher's age is excluded = the average age - 2 years
We have to find
teacher's age = ?
Lets take the average age of 10 students and their teacher be x = 20 years.
Now ,We have to find x
x = (sum of ages ) /(number of students+1)
20 = (sum of ages ) / 11
sum of ages = 20 × 11 = 220 years
The average age when the age of the teacher is excluded
= 20 -2 = 18 years.
18 = sum of ages of students / 10
The sum of ages of students = 18 × 10 = 180 years .
Now for Teacher's age = (sum of ages of students and their teacher) - ( sum of ages of students )
= 220 -180 = 40 years.
∴ Teacher's age = 40 years.
For more such questions ;
https://brainly.in/question/49878696
#SPJ3