Answer in 5 . 4 . 3 . 2 . 1 .....
 

The following is borrowed from [URL="http://www.npr.org/2016/10/16/497861459/when-it-comes-to-the-puzzle-dont-mail-it-in-just-exchange-a-letter"]here[/URL].
[QUOTE]Take the digits 5, 4, 3, 2 and 1, in that order. Using those digits and the four arithmetic signs — plus, minus, times and divided by — you can get 1 with the sequence 5 - 4 + 3 - 2 - 1. You can get 2 with the sequence (5 - 4 + 3 - 2) x 1.

The question is ... how many numbers from 1 to 40 can you get using the digits 5, 4, 3, 2, and 1 in that order along with the four arithmetic signs?

You can group digits with parentheses, as in the example. There are no tricks to this, though. It's a straightforward puzzle. How many numbers from 1 to 40 can you get — and, specifically, what number or numbers can you not get?[/QUOTE]Let's try to keep it with out powers or bases. Also, let's try to get variants for each number
Color any additions that you make.
[CODE] 1 = 5 - 4 + 3 - 2 - 1
2 = (5 - 4 + 3 - 2) x 1
[COLOR="Green"] 3 = (5 + 4) - (3 x 2 x 1)
4 = -5 + 4 + (3 x 2) - 1
5 = -5 + (4 x 3) - 2 x 1[/COLOR][/CODE]

I'll take 6 and pass it on...
 

6 = (5 - 4) * (3 * 2 * 1)

7 = 5 - 4 + 3 + 2 + 1

8 = 5 + 4 - 3 + 2 * 1

9 = 54 / 3 / 2 * 1 :rolleyes:

[SPOILER]Because 5+4+3+2+1 = 15, each odd number up to 15 is easy: just change one or more pluses into a minus. It is much more interesting to use a minimal number of signs (less than four; then obviously you will have some more than 1-digit numbers)[/SPOILER]

[QUOTE=Batalov;445264]9 = 54 / 3 / 2 * 1 :rolleyes:[/QUOTE]

Without cheating...

9 = (5 + 4) * (3 - 2 * 1)

10 = (5 + 4) + (3 - (2 * 1))

[B]11[/B] = 5 + 4 + 3 [B]-[/B] 2 + 1
12 = 5 + 4 + 3 * (2 - 1)
[B]13[/B] = 5 + 4 + 3 + 2[B] -[/B] 1
14 = 5 + 4 + 3 + 2 * 1
[B]15[/B] = 5 + 4 + 3 + 2 + 1
16 = 5 + 4 + 3 * 2 + 1

17 = (5 + 4*3) * (2-1)
18 = 5 + 4*3 + 2 - 1

19=(5*4)-(3/(2+1))
20=(5*4)+(3-(2+1)) or 20=(5*4*3)/(2+1)
21=(5*4)+(3/(2+1))

22 = (5 * 4) + 3 - 2 + 1