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Greg Ward
22nd May 2010, 11:54 AM
Place three common mathematical symbols between the digits:

1 2 3 4 5 6 7 8 9

So that the result equals 100
The same symbol can be repeated, but each repeat counts as one the three symbols you must use.
Rearranging the digits is not permitted.

Greg

Scott
22nd May 2010, 02:45 PM
1x(2+3)x4x5+6789 = 100
:U

Greg Ward
22nd May 2010, 03:53 PM
Perhaps not.....
Now try it using only 3 symbols (same symbol can be used more than once)


Greg

ajw
22nd May 2010, 04:39 PM
123-45-67+89 = 100

ajw

Scott
22nd May 2010, 04:50 PM
1x2x3x4+5+6-7+8x9

I wonder how many permutations?

Greg Ward
22nd May 2010, 04:53 PM
That was great!
Now try this one:


Place a standard mathematical symbol between 4 & 5 to get a number greater than 4 and less than 5.

ajw
22nd May 2010, 04:54 PM
There would be dozens of possible solutions if you don't limit yourself to 3 mathematical symbols. Even more solutions if you could use parentheses to force an order of calculation.

ajw

Scott
22nd May 2010, 04:57 PM
4 + 5 ≠ 4.5

What do I win? :D

Scott
22nd May 2010, 05:08 PM
Actually, still thinking about that one. Let me put one back at you.

Place a standard mathematical symbol between 4 and 5 to get a number greater than 1000.

ajw
22nd May 2010, 05:11 PM
Place a standard mathematical symbol between 4 and 5 to get a number greater than 1000.


Too easy. 4^5=1024


ajw

Greg Ward
22nd May 2010, 05:13 PM
You win the profit from my sale of 2 bicycles.

I sold one for $300 a loss of 25%
and another for a gain of 25%.

How much do you get?

Greg

ajw
22nd May 2010, 05:21 PM
That was great!
Now try this one:


Place a standard mathematical symbol between 4 & 5 to get a number greater than 4 and less than 5.

One answer is 4+log(5). Is that the solution you had?

ajw

Greg Ward
22nd May 2010, 05:34 PM
This one really is just a trick.
Place a decimal point between 4 & 5 and you get....... 4.5

A policemen has forgotten his log book and he spots 3 speeding cars. He has a good memory and notes their 4 digit number plates easily as they all contain the same 4 consecutive numbers:
one, the correct order, one the reverse and the other higgledy-piggledy.
He also notices the three numbers added together total 12,300.

What are the number plates?

Greg

ajw
22nd May 2010, 05:41 PM
This one really is just a trick.
Place a decimal point between 4 & 5 and you get....... 4.5

A policemen has forgotten his log book and he spots 3 speeding cars. He has a good memory and notes their 4 digit number plates easily as they all contain the same 4 consecutive numbers:
one, the correct order, one the reverse and the other higgledy-piggledy.
He also notices the three numbers added together total 12,300.

What are the number plates?

Greg

2345, 5432, and 4523

ajw

Scott
22nd May 2010, 06:33 PM
Oooh, hats off :2tsup:

4 + 5 ≠ 4.5. Technically I was correct?

Greg Ward
22nd May 2010, 06:40 PM
ajw. You've got to get out more......Hope you enjoyed the fun. I guess it's raining up there and maths isn't a bad way to spend an afternoon


sjt. I'll give it to you

One final one that combines history.

A Roman Emperor was born in 35BC and died on his birthday in AD 35.
What was his age when he died?

Greg

funkychicken
26th May 2010, 09:40 PM
71

Greg Ward
27th May 2010, 08:34 AM
Apparently, there is no '0' year (like the year 2000), so he was actually 69......

Greg

Swifty
27th July 2010, 06:35 AM
Oh...I thought the trick was that there was no Roman emporer born in 35BC:no:. There was one born in 63BC, another in 42 BC and the last one in 10 BC. :doh: But you are right :; about year zero. :2tsup: