[sheepman]

Was watching a countdown re-run at 5:30 this morning, neither of the contestants got it, is it that hard?

100 25 10 8 7 5 = 804

[matmat]

do the numbers have to stay in order?

[EricK]

For a solvable numbers game, that is pretty hard.

[naresh301]

matmat, on Sep 11 2008, 10:41 PM, said:

do the numbers have to stay in order?

I spent quite a bit of time under this assumption before realising that it is impossible...

Jlall said:

Spoiler

117*7=819

This was too hard

[matmat]

matmat, on Sep 12 2008, 12:41 AM, said:

do the numbers have to stay in order?

how about

(100-25-8) * (10+7-5)

[matmat]

Jlall, on Sep 12 2008, 12:53 AM, said:

I think matmats answer is way simpler than mine, not sure why I blanked on 67*12. Can we create a new subforum for countdown problems?

i'm still trying to get them in order :/

[sceptic]

I did it in 1 min 10 seconds,

rules of count down are 30 seconds ONLY and pen and paper no calculators, try you tube for loads more examples, if you can't do it in 30 seconds you have to give the nearest numbers you can get and who ever gets it or scores nearest wins

[EricK]

You don't have to use all the numbers though, do you?

In that sense (100-25-8)*(7+5) is the simplest solution. How easily gettable that is within the 30 seconds allowed is debatable.

Probably the easiest solution to find quickly is 100*8+7-(25+5)/10 or 100*8+7-(25-10)/5, but under time pressure it's easy to panic and think you "obviously" can't make 3 with 25,10 and 5.

[naresh301]

sceptic, on Sep 11 2008, 11:05 PM, said:

if you can't do it in 30 seconds you have to give the nearest numbers you can get and who ever gets it or scores nearest wins

It is pretty easy to get 803 and 805 in less than 30 seconds..

[EricK]

If you want a hard problem, use the same numbers (100,25,10,8,7,5) to make 923

[MickyB]

sheepman, on Sep 12 2008, 05:40 AM, said:

Was watching a countdown re-run at 5:30 this morning, neither of the contestants got it, is it that hard?

100 25 10 8 7 5 = 804

7-(25-10)/5+8*100

Wasn't timing, didn't feel like 30 seconds though

[NickRW]

For the record, you do not have to use all the numbers and you can use them in any order.

If you're reasonably facile with numbers, but not especially so, you should find that a few solutions kind of just jump out at you, some others can be solved in the 30 seconds, many you can get an answer close to the one wanted, and a few just leave you scratching your head!

Contestants in the TV program usually get some credit for getting close to the right answer (within 10 I think) provided their opponent doesn't get closer.

Nick