redimp
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« on: November 11, 2008, 09:59:18 PM » |
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Solving Double Inequalities
Ok guys, we have come so far with these but now we're a little bit stuck.
Here's the one we can solve and how we do it :-
13<2x+5<15 - by subtracting 5 we now have
8<2x<10 - by dividing the x value into the two outer numbers we get
4<x<5 which is the answer.
So how would we go about solving this one
x+13<3x+5<3x+11.
The answer is 4<x<3 (apparently)
Thanks in advance Pete and Shell
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Graham C
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« Reply #1 on: November 11, 2008, 10:05:13 PM » |
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14 year old? You sure it's not masters level applied maths?
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kinboshi
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« Reply #2 on: November 11, 2008, 10:08:26 PM » |
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How can x be greater than 4, but less than 3?
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'The meme for blind faith secures its own perpetuation by the simple unconscious expedient of discouraging rational inquiry.'
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action man
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« Reply #3 on: November 11, 2008, 10:08:52 PM » |
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xis 4.5
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bolt pp
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« Reply #4 on: November 11, 2008, 10:09:41 PM » |
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they wonder why kids skip school?
girls are cleverer than boys though, boys just want to play football and stuff(i was getting up to a lot of stuff at 14 that would put the modern day so called"hoodies"to shame) whereas girls seem more focused.
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bolt pp
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« Reply #5 on: November 11, 2008, 10:10:52 PM » |
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How can x be greater than 4, but less than 3?
magic x innit
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Jon MW
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« Reply #6 on: November 11, 2008, 10:27:51 PM » |
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x+13 < 3x + 5 < 3x + 11
subtract x+5
8 < 2x < 2x + 6
divide by 2
4 < x < x + 3
My apologies if I've missed anything but this makes more sense than 4<x<3
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Jon "the British cowboy" Woodfield
2011 blonde MTT League August Champion 2011 UK Team Championships: Black Belt Poker Team Captain - - runners up - - 5 Star HORSE Classic - 2007 Razz Champion 2007 WSOP Razz - 13/341
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Longy
Professional Hotel Locator.
Learning Centre Group
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Posts: 10064
Go Ducks!
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« Reply #7 on: November 11, 2008, 10:34:41 PM » |
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x+13 < 3x + 5 < 3x + 11
subtract x+5
8 < 2x < 2x + 6
divide by 2
4 < x < x + 3
My apologies if I've missed anything but this makes more sense than 4<x<3
Yup this looks right. Misprint in the answers no doubt.
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Rupert
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« Reply #8 on: November 11, 2008, 11:31:12 PM » |
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The answer is 4<x<3 (apparently) lol
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snoopy1239
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« Reply #9 on: November 12, 2008, 02:16:37 AM » |
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x+13 < 3x + 5 < 3x + 11
subtract x+5
8 < 2x < 2x + 6
divide by 2
4 < x < x + 3
My apologies if I've missed anything but this makes more sense than 4<x<3
Looks good. Original answer is clearly gibberish. I'd imagine they want it with as few 'x' as possible though.
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kinboshi
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« Reply #10 on: November 12, 2008, 09:48:13 AM » |
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x < x + 3 is particularly useful to know.
I think they probably have the correct answer, but they have made a mistake with the original statement. The same as the question to life, the universe and everything.
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« Last Edit: November 12, 2008, 09:50:59 AM by kinboshi »
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'The meme for blind faith secures its own perpetuation by the simple unconscious expedient of discouraging rational inquiry.'
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Sark79
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« Reply #11 on: November 12, 2008, 07:24:16 PM » |
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I feel ill after reading this thread. I really hate maths, it is so difficult and confusing. Words are much more fun than numbers. I was given Bill Chen's book about poker maths as a gift earlier this year and I flicked through it before donating it to pdsa in Kilmarnock a day later. I am ok with basic poker maths, but the maths in this thread hurts my head.
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