Quizing math & physics

Oliver · **Wed Mar 17, 2004 12:53 pm Quizing math & physics**

OK, I'll post a few mathematical questions and anyone may answer them. I'll also keep track of who gets the questions right first. The first person to get five questions right wins! (Hoping that there will be enough people trying!)

Question 1: Start with the number 1. If you keep on adding half of the previous number and keep on adding for ever, what number do you end up with?

1 + 1/2 + 1/4 + 1/8 + 1/16 + 1/32 + ... = ???

Thomas · **Wed Mar 17, 2004 1:07 pm**

Oliver · **Wed Mar 17, 2004 1:17 pm**

The correct answer to question 1 is indeed "2".

Winners so far:
choco_11: 1

Question 2: Same as question 1 but this time, alternate adding and subtracting the numbers.

1 - 1/2 + 1/4 - 1/8 + 1/16 - 1/32 + ... = ???

Thomas · **Wed Mar 17, 2004 1:20 pm**

So many people make this mistake... chocho_11,

Is the answer 'zero'?

Oliver · **Wed Mar 17, 2004 1:26 pm**

Sorry about that chocho_11. Won't happen again. It's just that choco (a chocolate paste) tastes so good!

No, the answer to question 2 is not "0".

Sarah Connor · **Wed Mar 17, 2004 6:29 pm**

Is it 0.65625?

F13RC3 · Lieutenant, Junior Grade Joined: 19 Feb 2004 Posts: 86

0.03125?

Achilles · **Thu Mar 18, 2004 12:23 am**

Oliver · **Thu Mar 18, 2004 12:57 am**

The correct answer to question 2 is indeed "0.66666... or 2/3".

Winners so far:
chocho_11: 1
Achilles: 1

Question 3: Data is on an alien planet in an alien laboratory. He's facing a console with 5 buttons. 3 of them each have 5 different symbols on them. The other two, only have 2 symbols.
Not knowing the access code, Data has to consider every single combiantion. Using his extreme intelligence, Data has ruled out 95% of the possibilities.
How many posibilities remain?

Leo Wyatt · **Thu Mar 18, 2004 5:37 am**

Is this algrebra? I am staying away from this lol

Thomas · **Thu Mar 18, 2004 8:13 am**

If came to 162.45, so 162?

Oliver · **Thu Mar 18, 2004 1:53 pm**

No, that's not it. I see your answer was a number with a decimal in it, then you rounded it off. As you know, the answer should be a whole number as it represents a certain amount of times.

Hint: If you have 1 button with 5 different symbols on it and you have to try every combination, then the answer is 5.
If you have two buttons with each 5 different symbols on it and you have to try every combination, then the answer is 5x5 = 25.
And so on...

Defiant · **Thu Mar 18, 2004 2:03 pm**

There are 120 possibilites. If Mr. Data ruled out 95% of the possibilites, then there would be 6 remaining. The answer is 6.

Now, I will do my best to explain my answer.

Basically, Data is facing 5 buttons, right? Therefore, it completely doesnt matter about how many symbols there are, since you are just pushing the button regardless. So, there are only 5 options. In math, you solve this type of problem by saying 5!, or 5 factorial, solved by multiplying 5x4x3x2x1. The answer to this is 120. 95% away, that means 5% left, which is 1/20th. 1/20th of 120 is 6 (120/20 = 6). This I did all in my head.

Josi Rockholt · **Thu Mar 18, 2004 3:55 pm**

Wow,your smart. I'm staying away from this topic. Not good at this math.

Oliver · **Fri Mar 19, 2004 2:53 am**

Hmmm. I think my question was't clear. This is my train of thought:

Data is looking at 5 different buttons with different symbols on each button. What I meant was that it would be possible for each button to take on the form of the different symbols. It's like a 5 digit number. The first digit has 10 possibilities ranging from 0 to 9. So do the other 4 digits. Each digit therefor has 10 possibilities. To try every combination, one needs to try 10 to the power of 5 possibilities, which equals 10x10x10x10x10.

In this example, 3 of the 5 buttons each have 5 possibilities (which equals 5x5x5) and the other 2 buttons each have 2 possibilities (which equals 2x2). Multiplying those two equals 5x5x5x2x2 = 500 possibilities. Cutting 95% off leaves 25 possibilities; which is the answer.

Using the factoral function implies you were thinking about in what order to press the 5 different buttons.

Now that I reread my question, I admit it might sound ambiguous. Sorry about that. You do get a point Defiant!

The first person to get 5 points wins the game.
Winners so far:
chocho_11: 1
Achilles: 1
Defiant: 1

Question 4: What is the daimeter of the circle of which its circumference is the same length as its area?

Thomas · **Fri Mar 19, 2004 11:10 am**

4<insert units here>?

Admiral_Tom_Paris · Commodore Joined: 01 Aug 2003 Posts: 1785

That's what I got too. so is it? (my mom helped me a little bit

)

Oliver · **Fri Mar 19, 2004 1:08 pm**

The correct answer to question 4 is indeed "4". At first, I thought I wrote radius, but it was the diameter we were looking for.

You get a point chocho_11 as you were the first to answer correctly.

Oliver · **Sat Mar 20, 2004 3:30 am**

The first person to get 5 points wins the game.
Winners so far:
chocho_11: 2
Achilles: 1
Defiant: 1

Question 5: If "0" is the first number and "1" the second number in the Fibonacci series, what is the 12th number?
The Fibonacci series is a series of numbers where every number (execpt for the first two) is the sum of the previous two numbers.

Thomas · **Sat Mar 20, 2004 5:07 am**

0 > 1 > 1 > 2 > 3 > 5 > 8 > 13 > 21 > 34 > 55 > 89

89?

Sarah Connor · **Sat Mar 20, 2004 9:05 am**

That's what I got too Chocho.

Oliver · **Sat Mar 20, 2004 3:56 pm**

The correct answer to question 5 is indeed "89". Chocho_11 gets one extra point.

The first person to get 5 points wins the game.
Winners so far:
chocho_11: 3
Achilles: 1
Defiant: 1

Question 6: Is the number, that we get when multiplying 5793 by 787, a prime number?

Sarah Connor · **Sat Mar 20, 2004 4:01 pm**

Answer to Q 6 no the number is not prime.

Oliver · **Sat Mar 20, 2004 4:24 pm**

The correct answer to question 6 is indeed "not prime". IluvCaptainKathrynJaneway gets one point.

The first person to get 5 points wins the game.
Winners so far:
chocho_11: 3
Achilles: 1
Defiant: 1
IluvCaptainKathrynJaneway: 1

Question 7: Look at the following formula:

f(x) = x^x (or x to the power of x)

If we fill in 3 we get: f(3) = 3� = 27
If we fill in 2 we get: f(2) = 2� = 4
If we fill in 1 we get: f(1) = 1

What do we get when we fill in 0? f(0) = ???

Captain CB · **Sat Mar 20, 2004 4:27 pm**

you get 1

f(0) = 0 to the power of 0 = 1