Question

There are 47 boys in a picnic group. The average age of the group is 12 years. However, if the teacher is included in the group, the average age of the group increases by 6 months. Find the age of the teacher.

Answer 1

Total of 47 boys=564

Total incl. Teacher = 12 1/2 x 48=600

age of teacher = 600-564=36

Ans is 36 years

Answer 2

The age of the teacher is 36

Step-by-step explanation:

$Average = \frac{\text{Sum of all observations}}{\text{No. of observations}}$

There are 47 boys in a picnic group. The average age of the group is 12 years.

So,$12 = \frac{\text{Sum of 47 boys ages}}{47}\\12 \times 47 =\text{Sum of 47 boys ages}\\564=\text{Sum of 47 boys ages}$

Let the age of teacher be x

if the teacher is included in the group, the average age of the group increases by 6 months.

New average = $12+\frac{6}{12}=12.5$

So,$12.5 = \frac{564+x}{48}\\12.5 \times 48=564+x\\(12.5 \times 48)-564=x\\36=x$

Hence the age of the teacher is 36

#Learn more:

The average age of a group of person going for picnic is 16 years. Twenty new persons with an average age of 15 years join the group on the spot due to which their average becomes 15.5 years. Find the number of persons initially going for picnic.

https://brainly.in/question/6786065