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#176 Re: Puzzles and Games » Metamorphosis » 2010-05-22 04:35:22

phrontister wrote:

TILP lol

Is that a real word? I can't find it anywhere. dunno

I dont really think so but it can be a surname is all that I could find googling. I thought TIGE was also a name coz searching for its definition doesn't return anything?!

TILE
TILL
TULL
GULL
GULF
GULP
TULP


phrontister wrote:

Bedzzzz!! sleep

sleep

#177 Re: Puzzles and Games » Metamorphosis » 2010-05-22 04:01:34

BOBS
BIBS
BIGS
TIGS
TIGE dunno
TILE
TILP lol
TULP


FOUR ZERO FIVE

#178 Re: Help Me ! » Products of numbers » 2010-05-22 03:43:25

You can find the other number by dividing 12 by 2 1/4.

2 1/4 = 2+(1/4) = 9/4

Now divide 12 by 9/4

12 ÷ 9/4 = 12 × 4/9 = 16/3 = 5 1/3

The other number is "5 1/3".


Welcome to MathIsFun! cool

#180 Re: Puzzles and Games » Add 13 more and post it forever. » 2010-05-21 23:37:27

6542 = dunno

6565 = 5 × 13 × 101 = (1×3×1)[sup]1+3+3+1[/sup] + 3 + 1


513101 is a Prime number.

135101  is a Prime number.

101513  is a Prime number.

#181 Re: Puzzles and Games » Probability of a Boy » 2010-05-21 23:14:23

Nope, don't worry, about that. The two dice are twins and so are the two coins and B and B. Twins already. Hope not , Vegas would come apart. Probability needs to work.

Consider the following experiments..
1. Throwing two identical unbiased dies and getting a sum of 11.
CASE-I: you get a 5 on dies-1 and 6 on dies-2
CASE-II: the numbers swap.
Both the cases are different and acceptable.

2. Throwing a dies twice and getting a sum of 11.
CASE-I: you get a 5 on throw-1 and 6 on throw-2.
CASE-II: a 6 on throw-1 and 5 on throw-2.
The cases, again, are different and acceptable too!

Now consider the experiment dealing with babies exactly identical in > height, weight, date/time of birth, choices (if that matters) but with different possible sexes except of course for the case that both are girls}...
CASE-I: both are boys.
CASE-II: one (which one?) is a boy and the other is not.

This is in no manner similar to stating that the probability of drawing a card from a pack of 52 cards and its being an A is 1/2 (either it is an A or it is not) because if it ain't an A then there are 12 other possibilities.
On the other hand, in case of the problem in context, no other outcomes are possible.


Normally, it doesn't have ANY business (whatsoever) with Vegas.
Probability works only on papers. Probability that you'r an Asian is 40%!

#182 Re: Puzzles and Games » Add 13 more and post it forever. » 2010-05-21 22:27:01

phrontister wrote:

Hey, ZHero! Did Joan change her phone number from a 6-digit positive one to an 8-digit negative one?!! She didn't tell me! sad

Ooops! One of the powers needed a fix...
(1×3)[sup]1+3+3+1[/sup] (1×3)[sup]1×3+3×1[/sup]
Done that!!! up

And i'll ask J to keep that number forever... Its propitious. wink

#183 Re: Puzzles and Games » Probability of a Boy » 2010-05-21 21:40:51

Hi;

Throwing a die one at a time Throw-1 and Throw-2
Throwing tow dies at once Die-1 and Die-2

Think distinguishability of the events plays an important role here!
Both the experiments are Similar because the events can be Differentiated!


I Can't think of any suitable example resembling "Twins" right now.... Hope there must be.

#185 Re: Puzzles and Games » Probability of a Boy » 2010-05-21 21:24:35

mathsyperson wrote:

Flip 2 coins at a time and the possible results are:

- Two heads
- Two tails
- One of each

The third result should come up roughly twice as much as the other two.

Got it since the Sample Space is {(HH), (HT), (TH), (TT)} and there are Two favorable outcomes for "One of each"! (I wouldn't go about the crazy idea of trying flipping a coin myself though sleep)


But this is fairly coz of one main reason... Coin-1 and Coin-2!!

Your next few words explain it More Clearly........

mathsyperson wrote:

The two extremes of the question are:
"I have two children. This one here, who I'm directly pointing at with no possiblility for confusion, is a boy. What's the probability that I have two boys?"
Answer 1/2.

"I have two children. One of them, and I'm not giving you any information about which, is a boy.
What's the probability that I have two boys?"
Answer 1/3.

Nice explication of the effect of distinguishableness. up


As i mentioned earlier.....

ZHero wrote:

I agree that the question is not framed properly since nothing is mentioned about who's younger/elder.

1/3 is possible for the case Child-1 (Younger) and Child-2 (Elder).

I'd set it that the probability is 1/2 if they are twins!?

#186 Re: Puzzles and Games » Add 13 more and post it forever. » 2010-05-21 20:55:46

6461 = 71 × 91

7191 × [(3-1)[sup]13[/sup] + (3-1)[sup]1×3[/sup] - (1×3)[sup]1×3+3×1[/sup]] - 6461 × [(3-1)[sup]13[/sup] - (3-1)[sup]3+1[/sup] + 1] = Joan's Telephone Number

#187 Re: Puzzles and Games » Probability of a Boy » 2010-05-21 19:19:13

I haven't yet thought about "a boy born on Tuesday" one...

But for the first one, the only possibilities are...
1. Both children are boys. ()
2. Both children are girls. (x)
3. One of the children is boy and the other one is girls. ()

I agree that the question is not framed properly since nothing is mentioned about who's younger/elder.
The question is analogous to possessing (order doesn't matter) two balls of different colors (say PINK and BLUE) and not to drawing two balls from two sacs of two different colored balls wherein the order of ball drawn matters!

#188 Re: Puzzles and Games » Probability of a Boy » 2010-05-21 18:57:30

DA@maa.org wrote:

So now you know the possible gender combinations are BB, BG, GB. Of these three possibilities, in two of them I have a boy and a girl, and in only one do I have two boys, so you should calculate the probability of my having two boys to be 1 out of 3, namely 1/3.

Out of the stated three combinatons BB, BG, GB, I think that BG and GB are identical!!
And hence, instead of 1/3, 1/2 should be correct! neutral

#189 Re: Help Me ! » Middle School Math » 2010-05-21 17:41:34

Raven17 wrote:

Suppose 1,000 people taught 2 others how to read in a year and then stopped teaching.  Then the 2,000 new readers taught 2 more each the next year and then stopped.  If the pattern continues, how many total readers would there be at the conclusion of 10 years?

Number of Readers Initially = 1000 = 1000×2[sup]0[/sup]

Number of New Readers..
at the end of 1[sup]st[/sup] year = (1000)×2 = 1000×2[sup]1[/sup]
at the end of 2[sup]nd[/sup] year = (1000×2)×2 = 1000×2[sup]2[/sup]
at the end of 3[sup]rd[/sup] year = (1000×2[sup]2[/sup])×2 = 1000×2[sup]3[/sup]
.
.
.
at the end of 10[sup]th[/sup] year = (1000×2[sup]9[/sup])×2 = 1000×2[sup]10[/sup]


Total Number of Readers at the End of 10 years...

1000×2[sup]0[/sup]+1000×2[sup]1[/sup]+1000×2[sup]2[/sup]+1000×2[sup]3[/sup]+...+1000×2[sup]10[/sup]

1000×(2[sup]0[/sup]+2[sup]1[/sup]+2[sup]2[/sup]+2[sup]3[/sup]+...+2[sup]10[/sup])

1000×(2[sup]11[/sup]-1)


NOTE: This an example of Exponential Growth!


#190 Re: Help Me ! » Middle School Math » 2010-05-21 12:34:52

Yes! You're Right!!

It should be 1000.(2[sup]11[/sup]-1)

#191 Re: Puzzles and Games » Perfect Squares.. » 2010-05-21 00:47:04

TheDude wrote:

No, there are infinitely many such squares.  Specifically, the square of 100z + {12, 38, 62, 88} for any non-negative integer z will end in xxxxxxxxx44.

you mean as in (1100+12)[sup]2[/sup] = 1236544

xxxxxxxab and (a,b)≠(00, 44)  tongue

Thanks Again!  up

#194 Re: Dark Discussions at Cafe Infinity » Song of the Day! » 2010-05-20 23:43:24

21[sup]st[/sup] May 2010

With or Without You (U2)

A cool song . . . . . .

I Love You Too! wink

#195 Re: Puzzles and Games » Word Game #66 » 2010-05-20 23:27:27

Where am i going wrong...

s-puzzled.gif


#196 Re: Help Me ! » Any puzzles? » 2010-05-20 23:09:40

Hi twister!

so far i've completed only...

1. The Missing Dollar (Part-1) in The missing dollar (& the 2 extra dollars) and am trying my best to find any answer to the second part...........

2. Joan's Telephone Number in Joan's telephone number & my YOB.

3. Self-Referential Aptitude Test.


I'm having a great time! wink

#197 Re: Puzzles and Games » Metamorphosis » 2010-05-20 22:42:22

phrontister wrote:

can we allow ZHero's puzzle before he's solved one first???!!!!!

I didn't know this rule... dunno I'll do one for you

LIFE FIND LOVE

LIFE
LINE
FINE
FIND
FINE
FIVE
LIVE
LOVE

roflol

#198 Re: Puzzles and Games » Add 13 more and post it forever. » 2010-05-20 21:20:44

Tigeree wrote:

Wow. Spooky, is it not?

waving.gif


6422 = 2 × 13 × 13 × 19


2131319 is a Prime number.

1321319 is a Prime number.

1313219 is a Prime number.

1913213 is a Prime number.

#200 Re: Help Me ! » Newton's laws » 2010-05-20 21:02:15

soha wrote:

One more here...

A rocket of mass

is blasted vertically upwards with an initial acceleration of
.Calculate the thrust of the rocket at lift off.

To calculate Thrust (Force) use...

Thrust = (mass × acceleration) + (weight of rocket)

weight of rocket is nothing but a downward force and needs to be overcome for the rocket to be able to move upwards.. hence is added to the required thrust)

Thrust = (4 × 10[sup]4[/sup] × 5) + (4 × 10[sup]4[/sup] × 9.8)

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