23
Oh, dude, that's just the mean of those numbers. You add them all up and divide by how many there are. So, like, you add 11 + 9 + 19 + 19, which gives you 58, then divide by 4 to get 14.5. That's the mean, man. Easy peasy.
28
-1
5 and -4
4 & 19... 4 x 19 = 76. 4 + 19 - 23.
23
79
79
41
19
19
There are numerous options. 20+1 19+2 18+3 17+4 16+5 etc
47
Oh, dude, that's just the mean of those numbers. You add them all up and divide by how many there are. So, like, you add 11 + 9 + 19 + 19, which gives you 58, then divide by 4 to get 14.5. That's the mean, man. Easy peasy.
19+4
OK. I've found it. You can too. Just add up all four numbers, and divide their sum by 4 .