Question

The average age of 19 boys in a class is 21 years.If the teacher's age is included,the average increases to 22 years. What is the teacher's age?​

Answer 1

Answer:

the ans. is 31 years .

Step-by-step explanation:

let the age of every student be x

(x₁ + x₂+ ....+x₁₉)÷ 19 = 21

( x₁+ x₂+....+ x₁₉) = 21×19

( x₁+ x₂+....+ x₁₉) = 399

let it be like this then

(x₁ + x₂+.....x₂₀ )÷ 20 = 22

(x₁ + x₂+.....x₂₀ ) = 22×20

(x₁ + x₂+.....x₂₀ ) = 440  

then

440 - 399 = teacher's age

41 = teacher's age

therefore teacher's age is 41 years

Hope this ans. becomes the BRAINLIEST !