Okay this problem is killing me because i couldnt figure it out from the sat i took on saturday. can anybody help.
There are three circles. The sum of their areas equals pi. The second circles radius is equal to 1/2 of the first and the third is 1/3.
So using A=(pi)r^2
Pi= (pi)r^2 + (pi) (1/2r)^2) + (pi)(1/3r)^3)
So you factor out the pi and divide by pi to get
1=r^2 + (1/2r)^2 + (1/3r)^2
Now i know it would be a lot easier with the multiple choice answers and you could just plug them in, but I forgot them and ran out of time to simply plug them in and this problem is killing me.
All help is appreciated
[QUOTE=CTJetFan92;3303314]Okay this problem is killing me because i couldnt figure it out from the sat i took on saturday. can anybody help.
There are three circles. The sum of their areas equals pi. The second circles radius is equal to 1/2 of the first and the third is 1/3.
So using A=(pi)r^2
Pi= (pi)r^2 + (pi) (1/2r)^2) + (pi)(1/3r)^3)
So you factor out the pi and divide by pi to get
1=r^2 + (1/2r)^2 + (1/3r)^2
Now i know it would be a lot easier with the multiple choice answers and you could just plug them in, but I forgot them and ran out of time to simply plug them in and this problem is killing me.
All help is appreciated[/QUOTE]
You do recognize that these are JET fans you are talking to correct???
We do not make up the top 5 percentile of achivers on written exams or so I would imagine.
That said, I have NO idea????
My best advice is to understand that you will NOT score 100 percent and accept the fact that THIS question is one of the wrong ones and lose NO SLEEP over it. The fact that it bothers you tells me you are probably one of the top performers on the exam anyway.
Best of Luck!!!
What college are you considering?
Last edited by southparkcpa; 10-12-2009 at 12:59 PM.
[QUOTE=CTJetFan92;3303314]Okay this problem is killing me because i couldnt figure it out from the sat i took on saturday. can anybody help.
There are three circles. The sum of their areas equals pi. The second circles radius is equal to 1/2 of the first and the third is 1/3.
So using A=(pi)r^2
Pi= (pi)r^2 + (pi) (1/2r)^2) + (pi)(1/3r)^3)
So you factor out the pi and divide by pi to get
1=r^2 + (1/2r)^2 + (1/3r)^2
Now i know it would be a lot easier with the multiple choice answers and you could just plug them in, but I forgot them and ran out of time to simply plug them in and this problem is killing me.
All help is appreciated[/QUOTE]
If it was for the radius of the big circle, the answer would be 6/7. You'd solve it the way you wrote, remembering the exponent went to the fraction as well as the variable.
Other than that, you'd have to remember what the actual question was.
[QUOTE=CTJetFan92;3303314]Okay this problem is killing me because i couldnt figure it out from the sat i took on saturday. can anybody help.
There are three circles. The sum of their areas equals pi. The second circles radius is equal to 1/2 of the first and the third is 1/3.
So using A=(pi)r^2
Pi= (pi)r^2 + (pi) (1/2r)^2) + (pi)(1/3r)^2)
So you factor out the pi and divide by pi to get
[B]1=r^2 + (1/2r)^2 + (1/3r)^2[/B]
Now i know it would be a lot easier with the multiple choice answers and you could just plug them in, but I forgot them and ran out of time to simply plug them in and this problem is killing me.
All help is appreciated[/QUOTE]
the answer was probably 6/7 though. i just wanted to show CTJetFan that you can do all the problems on the SAT without a calculator.
it gets too complicated when you start plugging long decimal numbers into your calculator. leave everything in fraction form, it's no coincidence that the answer is the square root of 36 over 49 (two perfect squares).
[QUOTE=OCCH;3303468]If it was for the radius of the big circle, the answer would be [B]6/7[/B]. You'd solve it the way you wrote, remembering the exponent went to the fraction as well as the variable.[/QUOTE]
That's what I said, 0.857! Jeez, where's the credit?!
No, .7386 doesn't quite work.[/QUOTE]
See now that I separated the r^2's from the quantity^2 without squaring the fractions. Knew I should've done it on paper first using clearer notation than my keyboard allows. Any more? That was fun, haven't tried one of those in many years
[QUOTE=loluchka80;3303649]you just gave him the answer with no work. i was trying to show him how to get it.
also, i bet none of the choices were 0.857. it was most likely 6/7. a calculator is unnecessary for the SAT.[/QUOTE]
[QUOTE=jetsNOW!;3303655]See now that I separated the r^2's from the quantity^2 without squaring the fractions. Knew I should've done it on paper first using clearer notation than my keyboard allows. Any more? That was fun, haven't tried one of those in many years[/QUOTE]
Here's a math problem I went through the other day with the girl working the McDonald's drive-thru. I placed an order which came to $7.61. I payed with a $20.00 bill. When the register opened she said is it ok I don't have any pennies. Remembering that the total ended in a 1, I said tha's OK and gave her a single penny from my ashtray which is filled with change. She responded with a perplexed expression and said, "Now I don't know how much change to give you." Resisting the urge to state, "Kill Yourself", I asked her how much change the register indicated. She responded $12.39. I then had to tell her that the proper change was $12.40. Solve for Y was she the one they put on the register and what does that say about the rest of the people working there.
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