Question

what is the answer
50 years or 40 years​

Answer 1

Answer:

hope it helps you see the attachment for further information

Answer 2

Answer:

The age of teacher was 50 years.

Step-by-step explanation:

The mean age of 35 students is 14 years.

The formula to compute mean is:

$\bar x=\frac{1}{n}\sum x_{i}$

Compute the sum of the ages of 35 students as follows:

$\bar x=\frac{1}{n}\sum x_{i}\\14=\frac{1}{35}\sum x_{i}\\\sum x_{i}=14\times35\\=490$

Now on adding the teacher's age the mean is 15 years.

Compute the sum of the ages of students and teacher as follows:

$\bar X=\frac{1}{n}\sum X_{i}\\15=\frac{1}{36}\sum X_{i}\\\sum X_{i}=15\times36\\=450$

Compute the age of teacher as follows:

$Age\ of\ teacher=\sum X_{i} - \sum x_{i}=540-490=50$

Thus, the age of teacher was 50 years.