Author Topic: Maths & Physics Help  (Read 59938 times)

Offline sweetsh

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Re: Maths & Physics Help
« Reply #270 on: May 09, 2009, 09:48:41 pm »
Dont worry

Offline Zain-Xa

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Re: Maths & Physics Help
« Reply #271 on: May 09, 2009, 09:57:20 pm »
i have another doubt.........

A student played a computer game 500 times and won 370 of these games.
he then won the next "x" games and lost none.
he has now won 75% of the games he has played.
Find the value of "x"

(pls show hw u got ur answer)
What can I do, to make it right
Falling so hard so fast this time
What did I say, what did you do?
How did I fall in love with you?


zzzzzZZZZZZzzzzzzzzz

I'll be strong.. I'll be wrong.. all the love goes on.. Oh im just a girl tryna find a place in this worLD..  Taylor swift <3

zara

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Re: Maths & Physics Help
« Reply #272 on: May 09, 2009, 10:02:52 pm »
its vry simple.....u do it like this...
total games played=500+x
games won=370+x
therefore,,,
370+x=(75/100)(500+x)
370+x=375+0.75x
375-370=x-0.75x
5=0.25x
x=5/0.25
x=20

chk d answer wid ms n if its rong lemme kno....
nemor doubts...plz don't hesitate ;)

Offline godfather93

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Re: Maths & Physics Help
« Reply #273 on: May 09, 2009, 10:05:13 pm »
ok now, the total number of games he's played is 500 + x.
the number of games he's won is 370 + x
The number of games he has won is 75% of (500 + x). (cause it says that he won 75% of the total games played)
hence, 370 + x = 75/100 * (500 + x)
          370 + x = 375 + 0.75 x
          0.25x = 5
          x = 20

Offline godfather93

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Re: Maths & Physics Help
« Reply #274 on: May 09, 2009, 10:05:50 pm »
guess we posted at the same time! lol :D

zara

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Re: Maths & Physics Help
« Reply #275 on: May 09, 2009, 10:07:06 pm »
yea......hehe :D

zara

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Re: Maths & Physics Help
« Reply #276 on: May 09, 2009, 10:07:59 pm »
actually urs is 3 mins late...lol

Offline Zain-Xa

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Re: Maths & Physics Help
« Reply #277 on: May 09, 2009, 10:12:25 pm »
thanx both of u   ;D
What can I do, to make it right
Falling so hard so fast this time
What did I say, what did you do?
How did I fall in love with you?


zzzzzZZZZZZzzzzzzzzz

I'll be strong.. I'll be wrong.. all the love goes on.. Oh im just a girl tryna find a place in this worLD..  Taylor swift <3

Offline Zain-Xa

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Re: Maths & Physics Help
« Reply #278 on: May 09, 2009, 10:15:04 pm »
My last Q for now  :P

a straight line passes through 2 points with co-ordinates (6,8) and (0,5).
Equation of the line??????????
What can I do, to make it right
Falling so hard so fast this time
What did I say, what did you do?
How did I fall in love with you?


zzzzzZZZZZZzzzzzzzzz

I'll be strong.. I'll be wrong.. all the love goes on.. Oh im just a girl tryna find a place in this worLD..  Taylor swift <3

Offline astarmathsandphysics

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Re: Maths & Physics Help
« Reply #279 on: May 09, 2009, 10:20:39 pm »
My last Q for now  :P

a straight line passes through 2 points with co-ordinates (6,8) and (0,5).
Equation of the line??????????

gadient m=(y2-y1)/(x2-x1)=(5-8)/(0-6)=1/2

y-y1=m(x-x1)
y-8=1/2(x-6) so y=1/2x+5
« Last Edit: May 09, 2009, 10:23:06 pm by astarmathsandphysics »

Offline godfather93

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Re: Maths & Physics Help
« Reply #280 on: May 09, 2009, 10:21:51 pm »
use the formula for the gradient: (y2 -y1)/(x2 - x1)
so it's (8 - 5)/(6-0)= 1/2
the y intercept is 5 because of the coordinate (0,5)
equation of line = y= 1/2x + 5
« Last Edit: May 09, 2009, 10:23:34 pm by godfather93 »

Offline godfather93

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Re: Maths & Physics Help
« Reply #281 on: May 09, 2009, 10:22:48 pm »
i agree you were quicker both times, but you got it wrong on this one. the gradient is a 1/2, not -1/2.

Offline astarmathsandphysics

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Re: Maths & Physics Help
« Reply #282 on: May 09, 2009, 10:24:02 pm »
I am a learner with latex that is why I sometimes get it wrong

Offline godfather93

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Re: Maths & Physics Help
« Reply #283 on: May 09, 2009, 10:24:33 pm »
sorry, i thought u were zara.... ;D

Offline Zain-Xa

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Re: Maths & Physics Help
« Reply #284 on: May 09, 2009, 10:26:56 pm »
thanx so is 1/2 or -1/2 ???
What can I do, to make it right
Falling so hard so fast this time
What did I say, what did you do?
How did I fall in love with you?


zzzzzZZZZZZzzzzzzzzz

I'll be strong.. I'll be wrong.. all the love goes on.. Oh im just a girl tryna find a place in this worLD..  Taylor swift <3