Arithmetic

[Peter Mabey]

Has it been stated that fractions are not allowable in the numbers round?
For example in the last round yesterday (August 25th) the target was 342, from 100,75,50,25,5,1.
Could one have said (75+1)x(5-25/50) ?

[Michael Wallace]

You have to work in integers, or at least you did when I was on the show (it says in the rules the contestants get sent before appearing).

Personally I always liked the idea of using fractions, as well as being able to use the numbers as powers, although that could get a bit silly

[Joseph Bolas]

Has it been stated that fractions are not allowable in the numbers round?
For example in the last round yesterday (August 25th) the target was 342, from 100,75,50,25,5,1.
Could one have said (75+1)x(5-25/50) ?

The rule is that you can not have negative numbers, decimal numbers, fractions, use numbers as powers etc.

[Charlie Reams]

The rule is that you can not have negative numbers

Are you sure about that? Negative numbers would never be useful (unlike fractions and powers) but as far as I know it's not invalid.

[Joseph Bolas]

The rule is that you can not have negative numbers

Are you sure about that? Negative numbers would never be useful (unlike fractions and powers) but as far as I know it's not invalid.

I know there have been a few times where Carol has explained the numbers games and I'm sure she said that you couldn't have negative numbers, but my memory ain't that good.

[Michael Wallace]

There's someone on here with a fresher memory than mine, I suspect, but I have vague memories of reading in the stuff they send you it mentioning negative numbers, but pointing out that it doesn't really matter because you can always just rephrase your solution so that the negative numbers don't come into it.

[Damian E]

Negative numbers and fractions are not allowed.

Somebody once tried to be different by dividing 10 by 4 to make 2.5, but it was swiftly disallowed.

[Peter Mabey]

I agree with the banning of powers, as the problem is to use the four standard operations, whilst negative numbers can always be avoided by a simple rearrangement.
However, it's likely that some combinations of target and given numbers could only be achieved using fractions - my example didn't use the 100, and though there are several solutions using all six, a different sixth number might not give any.

[Jason Larsen]

I thought division was allowed!

[Ralph Gillions]

I thought division was allowed!

Yes Jason division is allowed - as long as it does not result in a fraction.

[Jason Larsen]

Would someone please give me an example of division resulting in a fraction?

[Ben Wilson]

Would someone please give me an example of division resulting in a fraction?

3/4=3/4.

[Jason Larsen]

So, Ben, in other words if you say "over" when declaring your solution you probably won't get any points.

[Gavin Chipper]

Negative numbers and fractions are not allowed.

Somebody once tried to be different by dividing 10 by 4 to make 2.5, but it was swiftly disallowed.

One wonders why he would do this if it's made clear in the rules.

[Gavin Chipper]

Would someone please give me an example of division resulting in a fraction?

3/4=3/4.

Brilliant.

[Jason Larsen]

If you say anything like, 3 over 4, you probably don't get any points. Do you?

[Gavin Chipper]

If you say anything like, 3 over 4, you probably don't get any points. Do you?

You won't. Obviously if someone says something like "200 * 3 / 4 = 150" then Carol would grill them about whether the 3/4 was in brackets or whether they meant 600/4, but I think the case would ultimately be judged on how quickly they said each bit and where the pasues were.

[Joseph Bolas]

You won't. Obviously if someone says something like "200 * 3 / 4 = 150" then Carol would grill them about whether the 3/4 was in brackets or whether they meant 600/4, but I think the case would ultimately be judged on how quickly they said each bit and where the pasues were.

I think in that situation, the contestant would most likely say something like 200 x 3 = 600, and then say / 4 = 150.

[Jason Larsen]

Carol is one inquisitive one, isn't she?

[Kirk Bevins]

If you say anything like, 3 over 4, you probably don't get any points. Do you?

I think you may be getting confused here, Jason. 3/4 (pronounced 3 over 4 or 3 divided by 4) equals three quarters (or three fourths in USA). It's a handy notation and helps people (although in saying this, the majority of kids nowadays struggle to do 3 divided by 4 and don't realise it's three quarters!). You can not have this because it is a fraction.

Saying 8/4 (pronounced 8 over 4 or 8 divided by 4) is allowed as, even though 8/4 is still a fraction (called an "improper" fraction), the answer is 2 (a whole number and not a fraction, like 3/4).

In short, the word "over" IS allowed - just not if the result ends in a number that is not whole (a "fraction")

[Charlie Reams]

You might say that Countdown only allows round naturals, but you should definitely Google that to make sure.

[Jason Larsen]

So, if you use fractions in your answer that is not allowed?

[Kirk Bevins]

So, if you use fractions in your answer that is not allowed?

Correct. Remember 8/4 is technically still a fraction but I know what you mean - you are only allowed to deal with whole numbers.

[Jason Larsen]

So, in your case, Kirk, it would be, "8 divided by 4."

[Kirk Bevins]

So, in your case, Kirk, it would be, "8 divided by 4."

Yes it would, but you can say that as "8 over 4" and that is fine. "Over" means divide in this context.

[Jason Larsen]

So, as long as you don't use a fraction, you get points.

[Joseph Bolas]

If you say anything like, 3 over 4, you probably don't get any points. Do you?

So, if you use fractions in your answer that is not allowed?

So, as long as you don't use a fraction, you get points.

It doesn't matter how you word your questions, the answer is always going to be the same.

If you are going to divide two numbers in your solution, you have to make sure that when you divide one number by the other (starting with the larger number first), the result is a whole number (eg 8 / 4 = 2). If it doesn't then, it's never going to be allowed (eg 3 / 4 = 0.75 or 4 / 3 = 1.33333...). Also divided by and over mean the same thing.

So you can have fractions if the end result of the division is a whole number, but not if the end result is a decimal.

[Jason Larsen]

Thank you, Joseph!

Now, I completely understand that!