Respuesta :

gustanika
for example, n is the number we want to find

The sum of the four numbers divided by 4 is equal to the mean.
the sum/4 = mean
(12 + 50 + 48 + n)/4 = 30
(110 + n)/4 = 30
(110 + n) = 30 × 4
(110 + n) = 120
n = 120 - 110
n = 10

The fourth number is 10