Question

The average of 3 numbers is 9. If the average of first 2 numbers is 12. What is the third number ? ​

Answer 1

answer

Step-by-step explanation:

The third number is 3

Answer 2

Answer:

3

Step-by-step explanation:

let the three numbers be a, b, c

(a + b + c)/3 = 9

multiply by 3

a + b + c = 27 ... (1)

given,

(a + b)/2 = 12

multiply by 2,

a + b = 24

substitute a + b = 24 in (1),

we get,

24 + c = 27

c = 27 - 24

c = 3