AMC10/12A

Who took the AMC10/12??? Did you meet your expectations?

Scores are not yet out, so please tell me if they are out :)

Thank You

#AMC #10 #12 #AIMEQUALIFICATIONS #AIMEBASH

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Math	Appears as
Remember to wrap math in `$` ... `$` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
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Comments

You can find the answer key online with a google search. I exceeded my expectations! The test had beautiful problems, like #25, (which I skipped)

Daniel Wang - 7 years, 4 months ago

Oh Thanks :)

Bob Yang - 7 years, 4 months ago

The AIME cutoff's going to have to be 120 this year.

Tristan Shin - 7 years, 4 months ago

I'm mad at myself for making FOUR stupid mistakes:

Forgot to add the original 35 miles (#11)
For the palindrome question, I added all $abc$ rather than $abcba$
For the arith/geo sequence question, forgot $a<b<c$
For question 24 with the absolute values (which was stupidly easy and didn't deserve to be question 24) I thought $f_0 (x)$ was $f_1 (x)$ !

But it's okay. I'm taking the 12B next week too. (I got a predicted 102 on this one, sadly)

Favorite problems: Question 21 and 23.

Question 21 because it's one of those "looks hard but isn't" questions

Question 23 because it's a great question.

Solution 23: Note that $\frac{1}{99} = .\overline{01} = (\frac{1}{100} + \frac{1}{10000} + \dots$ , so $\frac{1}{99^2} = (\frac{1}{100} + \frac{1}{10000} + \frac{1}{1000000} + \dots) (\frac{1}{100} + \frac{1}{10000} + \frac{1}{1000000} + \dots)$ .

Multiplying the first term, $\frac{1}{100}$ , by the whole of $(\frac{1}{100} + \frac{1}{10000} + \frac{1}{1000000} + \dots)$ . ) yields the repeating decimal $0.00\overline{01}$

Multiplying the second term yields $0.0000\overline{01}$ , and so forth. Thus, the decimal looks like so:

$0.000010203040506070809101112131415\dots969799$ -- note that $98 + 99 + 100$ at the end turns into $990000$ .

Adding it up, the sum of the first $9$ natural numbers occurs $10$ times, so that's $450$ . Then the digit $1-9$ appears as the "tens place" $10$ times each, so that's another $450$ . Subtract $8 + 9 = 17$ since $98$ isn't counted to get $883$ as the answer. $\blacksquare$

Michael Tong - 7 years, 4 months ago

i tooko the 10A, and i got a 114. Not as good as I wished it could be, but I am overall satisfied

@Michael tong- you're 23, how you take the amc12

Jeremy Lu - 7 years, 4 months ago

read my profile -- "I'm 17, not 23!"

Michael Tong - 7 years, 4 months ago

AMC12....expecting a 118.5, enough to make the AIME. During the test, I only focused on the first 20 questions(as I mentioned in my strategy), I skipped number 8 on due to the confusing wording of the problem, later I found out all of other participants in my school was able to do that problem. Next there was number 18, which twisted up my brain......

Other than these, I feel satisfied since I didn't leave any counting and geometry problems blank :)

Xuming Liang - 7 years, 4 months ago

I got a 132, but I made a stupid mistake on number 4. It was really easy this time; previously, I had scored 1.5 less than the cutoff almost every time.

Trevor B. - 7 years, 4 months ago

On the AMC 10, I did my modular arithmetic wrong and got #2 wrong...

Tristan Shin - 7 years, 4 months ago

lol same here :P

Bob Yang - 7 years, 4 months ago

I feel dumb... Made a dumb arithmetic mistake on #17 [36+9=42] and ended up with 112.5

Jerry Lee - 7 years, 4 months ago

I got 130.5 on AMC 10. Made a stupid mistake on number 4 (multiplied by 2). Finished the first 22, missed one. I heard from my friend that #23 was easy, but otherwise, I think I did well. The AMC answers are all on AoPS, so you can go on there to check. Well, I'm taking the AMC 12B next week. Hopefully, I can get at least a 110.

Alan Hu - 7 years, 4 months ago

Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$