sure they had calculators in 1914, called an abacus.

So what is the answer?

Fifteen.

(Didn't mean to spoil it - if that's what I did.)

you are correct! Can you show your work? KIDDING!

My guess is 5!

Two wrongs (15 and 5) don't make a right. LOL

Why wouldn't a fourth of twenty be 7.5?

Who said it wouldn't, Fun2BHere? That's the correct answer! You get an A+.

For those who want to know, here's how I did it: Three is half of six, so if you follow the question, 10 would be 1/3 of 20. If 10 is 1/3 of something, what would 1/4 of that something be? We know that 10 is in fact 1/3 of 30, and 1/4 of 30 is 7.5. Voila!

Way to go F2BH!!!!

I'm lost..........too hard for my pea brain to figure out.

Oh, I'm glad I got it right. I guess I was confused by those posters upthread from me who said it was 15. I calculated a little differently than you did, Alisande. I looked at it from the perspective that if 1/3 of 6 is 3, that is 150% of the value 2 that would be 1/3 of 6 in base 10. I then applied that factor to 5 which would be 1/4 of 20 in base 10. 1.5 times 5 equals 7.5.

I think it "stumps" college professors in that as-stated the question doesn't contain enough information to definitively point to any one answer.

It essentially constructs a new mathematical operator named "of" such that when applied to the two operands "a third" and "six" produces the answer "three". Then without any further information it asks what "a fourth" "of" "twenty" is.

However unless you assume that the "of" operator behaves similar to the multiplication operator, and further assume a definition for another datapoint, such as "zero" "of" "zero" is "zero", then literally any number in the world could be the answer to "a fourth" "of" "twenty"

So the professors may have said "I cannot give an answer, because the problem, as-stated, doesn't contain enough information." and the newspaper writers exclaimed "Ah ha! we've stumped them."

A similar problem with slightly more information specified:

Assume an operator named "blah" such that:

"Zero" "blah" "zero" equals "zero"
"two" "blah" "two" equals "four"
"one point five" "blah" "three" equals "four point five"

then what is:
"four" "blah" "five"

Note, I guarantee that the first person to come up with an answer to my question will be wrong.

Good one, Fun2BHere! Another one of my friends said it this way:

1/3 x 6 = 2 x 1.5 = 3. Soooooooooo......1/4 x 20 = 5 x 1.5 = 7.5.

Bob, your problem doesn't make it clear what "blah" stands for, so I'm not going to hazard a guess.

I think it "stumps" college professors in that as-stated the question doesn't contain enough information to definitively point to any one answer.

All I know is . . . Fun2BHere and I got it right. :-)

I also got 7.5.

Equation 1: (1/3)6n = 3
leads us to n = 1.5
Equation 2: (1/4)20n = ?
Substitute the answer for n from Equation 1 into Equation 2.
(1/4)20(1.5) = 7.5

Alisande, although one may do math in their head the way you have written it and arrive at a correct answer, what you have written is incorrect. Each step should be it's own line. 1/3x6 = 2, but it does not equal 2x1.5 = 3, which is what you have written.

I was watching "Big Bang Theory" at the time and channeling my inner Sheldon Cooper.

That is a completely reasonable answer to the original question, and most likely the one the newspaper had in mind. I was just pointing out that, pedantically speaking, the problem is insufficiently specified.

Just as if someone asked "how long would it take for an object that masses 1 kg to fall from height of 100 meters?" Without stating that the object is motionless to begin with, that object is such that air resistance can be neglected, and that the experiment is taking place on the surface of the earth, the question cannot be definitively answered.

For my question there are two relatively simple answers, and whichever one someone chooses first, I'll say I meant the other.

Bob: 9 and 20?

Alice, your post confused me more than the original problem. This is probably because I'm not even close to being a math whiz. Although I was very good in math in high school, high school was a loooong time ago. :-)

I wrote this above:

For those who want to know, here's how I did it: Three is half of six, so if you follow the question, 10 would be 1/3 of 20. If 10 is 1/3 of something, what would 1/4 of that something be? We know that 10 is in fact 1/3 of 30, and 1/4 of 30 is 7.5. Voila!

And you wrote:

Alisande, although one may do math in their head the way you have written it and arrive at a correct answer, what you have written is incorrect. Each step should be it's own line. 1/3x6 = 2, but it does not equal 2x1.5 = 3, which is what you have written.

Sorry, but I don't get what you mean. If someone could follow those steps in their head and arrive at the correct answer, how can my steps be wrong? And I don't see where I wrote 2x1.5 = 3.

BTW, I'm not questioning your knowledge of math, which is clearly superior to mine.

Gosh, I'm glad I don't "do" math! Fun watching, tho!

Alisande,

Yes those are both of the answers.

Decades ago my father was explaining how to use his slide rule and was showing how to use it to do multiplication. I asked whether it could do addition, and he said no. I then chose two numbers 1.5 and 3 to try to show that it could add, and looked up the answer and got 4.5, see dad it can add after all. It took him a while to explain my mistake.

-Bob

This post was edited by bob_cville on Thu, Apr 17, 14 at 23:29

Alisande, I am sure if you and I were sitting down with paper and pencil that we'd come to the agreement that we were both doing the same math. It just looks different.

Fun2B explained it well. The first part of the question tells you you are working with a "wrong" answer." If one third of six is three" when we know the truth is one third of six is two. The rest follows as Fun2B explained.

I have always, and always will, detested math.

Just reading the original question/problem has fired a headache in my brain.

Caroline, I get the same reaction if I try to contemplate the universe. It's just too big!

Jannie, the first part does not say anything is "wrong." It simply lets the reader know something is missing if that statement is true.

I'm sure I've posted this before, but my math 'disability' became evident in grade 2 or 3, when we were given some simple problems to solve. We were asked "If 3x2=6, what does 2x3=? and similar equations to teach us that any number x another number equals the same answer, if you reverse the figures. But when I got to "If 0x7=0, what does 7x0=? I answered 7.

We were first taught to imagine apples replacing the figures in our multiplication equations. So I realized "No apples multiplied by four times that amount still gives you no apples. But to me, four apples multiplied by zero times that amount still leaves me with my original four apples. When it was marked wrong, I asked the teacher "But what happened to the four apples I started with? Thus began my career path towards law, instead of engineering, lol!

yep... still true...Math gives me a headache...

The problem statement is:

"If a third of six were three,
What would a fourth of twenty be?"

Right at the outset, there is a problem because 1/3 of 6 is 2, not 3. So at the beginning, we have to accept that an error is true. We can set up a correction ratio thusly:

1/3 x 6 x n = 3 and n is 1.5 or 3/2.

Inserting this factor into the second part of the proposition:

1/4 x 20 x n OR
1/4 x 20 x 3/2 = 7.5

Using this logic, the answer is 7.5 or 15/2.

However, this may be a trick problem and the answer is not gotten by math, but by some other association such as alphabetic order. The original statement violates a rule of ordinary math, therefore it is illogical as Mr. Spock might say.

I agree with Bob. The problem is not defined enough to work it one specific way.

"If a third of six were three,
What would a fourth of twenty be?"

I thought it was a trick question to say something simple the hard way. I took it to mean you simply had the numbers 1- 6. The third number was three. Using this logic, the fourth number of 20 would be 4.

Hurts my head!!

Hurts my head!!