+0

# number puzzle for bored forum attendees :))

0
510
29
+91450

Here is a puzzle to entertain you for a little while Complex, and anyone else who would like to try:)

No cheating - it has to be your own solution, not google's or your mum's. etc    LOL

Use the numbers

2,3,8,7,6, and 5 to make the number 945.

You do not have to use all  the numbers but you are not allowed to use any more than once.

All standard operations are allowed.

Good luck :)

Melody  Dec 13, 2015

#7
+1311
+5

Here are some I find that = 945

(5-2)*7*(6*8-3)

(3+2*5*6)*(7+8)

(8*(6*7-2)-5)*3

((2+6*8)-5)*3*7

(3+6*8/2)*5*7

Dragonlance  Dec 13, 2015
edited by Dragonlance  Dec 13, 2015
Sort:

#1
+405
0

Thanks!!

Complex  Dec 13, 2015
#2
+140
+5

I think I have it

945 is the solution

2,3,8,7,6,5 are the variables

6+3=9

8/2=4

5=5

945 this was of the top of my head but seven is usless.

Kallamoar  Dec 13, 2015
#3
+405
0

The "No using moe than one of each number" rule is k*****g me!

Complex  Dec 13, 2015
#4
+405
0

Kallamoar: I think you have to actually add them up or something like that.

Complex  Dec 13, 2015
#5
+140
0

If complex is right then I have run out of ideas at the moment.

Kallamoar  Dec 13, 2015
#6
+91450
0

Hi guys,

You made the digits Kallamoar but you didn't really make 945.

I'll give you the points for you good effort and because these types of instruction are often unclear.

Hint:

There is more than one solution but when I did it I used a subtraction sign.

I could have done it slightly differently and used 2 subtraction signs :D

Melody  Dec 13, 2015
#7
+1311
+5

Here are some I find that = 945

(5-2)*7*(6*8-3)

(3+2*5*6)*(7+8)

(8*(6*7-2)-5)*3

((2+6*8)-5)*3*7

(3+6*8/2)*5*7

Dragonlance  Dec 13, 2015
edited by Dragonlance  Dec 13, 2015
#8
+5

(7^2+8+6)*3*5=945

Hope this is right! : D

Guest Dec 13, 2015
#9
+1311
0

No. You cant use 7^2 because that mean you are using the 7 twice like 7*7. It have to be in there twice to use it twice.

Dragonlance  Dec 13, 2015
#10
+91450
0

Thanks Dragonlance, that is a great answer.

Plus, it is totally different from the one I came up with :)

2,3,8,7,6, and 5 to make the number 945.

I'll show other people how you may have come up with your answer.

First I will be a bit lazy and let the web 2 calc find the prime factors of 945

factor(945) = (3^3*5)*7

so

945=7*3*3*3*5

945=7*5*3     *9   Nope, I cannot make 9 with the ones I haven't used

that 7 doesn't look very versitle.  mmm

945=7*3      *5 *9

I do not have another 3 or a 9 so how else can I make 45 with  2,8,6,5

6*8=48   so 6*8-3 = 45 and I can make a 3 with  5-2

so         45 = 6*8 - (5-2)

so     945 = 7*3*[6*8-(5-2)]

See how I got a very slightly different answer to Dragonlance.   Because I used 5-2=3 in a different spot.

But our answers really have the same derivation.

So

945 = 7*3*[6*8-(5-2)]       Melody

945 = 7*(5-2)*[6*8-3]        Dragonlance

Now the answer that I originally had is quite different.  It involves at least one minus sign and a power and it uses all the numbers :/

Can anyone else find it?

Melody  Dec 13, 2015
#11
+91450
0

No Dragonlance our guest's answer is REALLY good!

5 stars for you!

saying that you cannot have  7^2 because it is like 7*7

is like saying that you cannot have 7*2 because that is the same as 7+7

So you can see that is nonsense :)

It is STILL different from my (2) answers  ://   So ther are MORE answers :)

Melody  Dec 13, 2015
#12
+1311
0

Sorry! I not know you can use exponents for this I thought it was just these +-*/ you could use.

His answer is really good then.

Dragonlance  Dec 13, 2015
#13
+91450
0

Yes Dragonlance, often you can only use + - * and / for these but I decided to allow more this time. :)

I did say "All standard operators are allowed"    :D

Melody  Dec 13, 2015
#14
+1311
0

OK I thought standard standard operators were only just +-*/

Do that mean I can use hyperbolic cosine and the Gama function?

If I use the standard Dragonlance function then I can make hundres of answers real easy. :) hahaha

Dragonlance  Dec 13, 2015
#15
0

What!!!!!! Can ya explain in slow motion to my stupid brain how ya got that answer. ( more than ya did already.) ðŸ˜‹

Guest Dec 13, 2015
#16
0

Did yo spell bored right? Or did yo mean it literally, like if yo bored? Instead of for example a business board.

Guest Dec 13, 2015
#17
+91450
0

I think I spelt is as I intended.   :D

Business cards are made of (card)board and they may be boring to some people but they do not normal hang out on maths boards (or forums)

Melody  Dec 13, 2015
#18
0

Sorry I read it with a different meaning. Meaning I've been goin with my mom to her stupid board meetings far too much.ðŸ˜€

Guest Dec 13, 2015
#19
+91450
0

Yes, I did realize that halfway through my response. I thought "maths boards" and the penny dropped :))

Melody  Dec 13, 2015
#20
+91450
0

Like I said, I know at least one more answer (2 very slightly different versions of the same thing really)

Here is a big hint:    1000-55=945

Melody  Dec 13, 2015
#21
+91450
0

Guest #15

Are you still on the forum?

If you are about and still want me to try and explain more then I will do that.

I need to here you 'voice' though :)

Melody  Dec 13, 2015
#22
0

I am still,on the forum but I stink at math that is above a 6th grade level. I'm in 7th grade so,it is sad. You probabaly do not want to waste time trying to explain it to me.

Guest Dec 13, 2015
#23
0

Is your profile pic of birds? Originally I thought it was spider man but now I am not sure...

Guest Dec 13, 2015
#24
+91450
0

Hi guest #22,

How about I try and explain with an easier one.

Let the numbers be 2, 3, 5, and 8  and the magic number that you have to make is 18

Just maybe you might be able to make it just by multiplying things together.

So I will look for all the prime factors of 18

18=2*3*3

we have the 2 and we have one 3

and we have 8 and 5  is we put them together as (8-5) then we have another 3

so one answer would be     18=2*3*(8-5)

Maybe you would like to try this one.    (This is not for big kids who are good at maths)

The numbers are  1,4,2,3,and 6 and the magic number is 27

If you answer this question copy the QUESTION into your post so we know what you are answering :)

Melody  Dec 13, 2015
#25
+91450
0

Hi Guest #23

No I am not spiderman

My icon is of 2 Crimson Rosellas (parrots). They live in the Blue Mountains which is not far away form where I live in Sydney :)

Maybe they are red and blue because THEY want to be spiderman  !!?!!

Melody  Dec 13, 2015
#26
0

I'm just gonna accept that I'm an idiot. Cause I didn't understand that one either...

Oh well that is why I'm gonna teach history. Or kindergarten math. Hahaha.

Well I have to go to church now so don't waste your time trying to make me understand something I am incapable of understanding. ByeðŸ˜€

Guest Dec 13, 2015
#27
0

I like your birds better than Spider-Man. Spider-Man is weird in my opinion. As are all super heroes...

Guest Dec 13, 2015
#28
+91450
0

I could not teach history effectively if my life depended on it.

We are all good at different things.  You have your talents the  same as I have mine :))

Enjoy church :)

Melody  Dec 13, 2015
#29
+91450
0

QUESTION:

Use the numbers

2,3,8,7,6, and 5 to make the number 945.

945 = 7*3*[6*8-(5-2)]       Melody

945 = 7*(5-2)*[6*8-3]        Dragonlance

945= (7^2+8+6)*3*5        guest

945 = (2*5)^3 - (6*8+7)      Melody

945 = (2*5)^3 - 6*8 -7        Melody  (really the same as the last one)

Melody  Dec 14, 2015
edited by Melody  Dec 14, 2015

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