Oh wonder i couldnot do this although i have given a lot of times.
just use only one operator mean you don't have to use one opretor more than once.
you have to keep also order of mathmatics, example while you are trying multiplication is more precedence than addition and substraction... etc
2007-02-15 02:34:14 · 10 answers · asked by Nebrom 1 in Science & Mathematics ➔ Mathematics
4 + 4 + 4 + 4 + 4 = 20
4 * 4 + 4 - 4 + 4=20
2007-02-15 02:40:05 · answer #1 · answered by Alias 2 · 0⤊ 2⤋
4+4+4+4+4=20
2007-02-15 02:43:16 · answer #2 · answered by s madhavan 1 · 0⤊ 2⤋
4+4+4+4+4=20
2007-02-15 02:40:10 · answer #3 · answered by Anonymous · 0⤊ 2⤋
4*4-4+4+4=20
2007-02-15 02:43:21 · answer #4 · answered by tav911@ameritech.net 2 · 0⤊ 2⤋
Assuming that you HAVE to use + - * / exactly ONE time each and you have to preserve order of operations AND you can not use parentheses to force the order of operations differently...
...it can not be done. The following is cut/paste from excel where I used all 24 combinations of + - * / between the five 4's:
4+4-4*4/4=4
4+4-4/4*4=4
4+4*4-4/4=19
4+4*4/4-4=4
4+4/4-4*4=-11
4+4/4*4-4=4
4-4+4*4/4=4
4-4+4/4*4=4
4-4*4+4/4=-11
4-4*4/4+4=4
4-4/4+4*4=19
4-4/4*4+4=4
4*4+4-4/4=19
4*4+4/4-4=13
4*4-4+4/4=13
4*4-4/4+4=19
4*4/4+4-4=4
4*4/4-4+4=4
4/4+4-4*4=-11
4/4+4*4-4=13
4/4-4+4*4=13
4/4-4*4+4=-11
4/4*4+4-4=4
4/4*4-4+4=4
There are ways to do this if you can use parentheses or other different operations but not with the constraints you gave.
2007-02-15 03:29:13 · answer #5 · answered by Will 4 · 0⤊ 0⤋
4+4+4+4+4 = 20
You may be thinking of the problem of making 20 out of FOUR 4s, not FIVE of them. In that case, your answer can't be had with just addition, subtraction, multiplication and division. But you can do it with factorials:
4! + 4 - 4 - 4 = 20
----------------------
Note: if you haven't run into factorials, here's what they are:
1! = 1
2! = 1 x 2
3! = 1 x 2 x 3
4! = 1 x 2 x 3 x 4
5! = 1 x 2 x 3 x 4 x 5
etc.
2007-02-15 02:40:03 · answer #6 · answered by K ; 4 · 0⤊ 1⤋
Can't be done, there are only 24 different ways, the closest you can get is 19 i.e.
4 - 4/4 + 4*4
2007-02-15 02:53:28 · answer #7 · answered by Steven Z 4 · 1⤊ 0⤋
4+4+4+4+4=20
2016-03-29 07:27:50 · answer #8 · answered by Anonymous · 0⤊ 0⤋
hmmm lets see...this is tough.....
4+4+4+4+4=20
2007-02-15 02:43:35 · answer #9 · answered by Anonymous · 0⤊ 2⤋
4(4/4)*4+4=20
use BODMAS rule!!!!
and no operation is repeated!!!!
2007-02-15 02:44:05 · answer #10 · answered by nehulstyagi29 2 · 0⤊ 2⤋