Question

the mean of two numbers is 13. if one of them is 20, than find the other ​

Answer 1

Answer:

other number = 6

Explanation:

let , the other number = b

then ,

mean = sum of observations/ no. of observations

13 = ( b + 20) / 2

13 × 2 = b + 20

26 = b + 20

26 - 20 = b

6 = b

hence , other number = 6

Answer 2

Explanation:

Given,

Mean of two numbers (x)= 13

Total numbers (N)= 2

here, let the other number be A

mean(x) = Σx / N

or, 13×2 = 20+A                  {hint- Σ x= 20+A)

or, 26 - 20 = A

A = 6

Therefore, the other number is 6.