If the mean of the four numbers 2x and 12 is 10, then x is

4

Step-by-step explanation:

The mean of 2x and 12 is (2x+12) / 2, so we get the equation:

(2x+12) / 2 = 10 = >

x+6=10

x = 10-6 = 4

* Your question states four numbers, but you write only two ... the answer could be wrong because of that.