Chapter 17
Chapter 17
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Translator: Ace
Chapter: 17
Chapter Title: KMO Second Round Exam
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The KMO second round exam was held at KAIST.
I'd been worried about having to go to Seoul, but fortunately, testing centers were set up in every province.
It's not that I hated Seoul, but the traffic was always a nightmare, and the air quality made me feel suffocated every time I visited.
"I'll do my best!"
"Good luck! Call me when you're done!"
The university main gate was too crowded, so I got out early instead of going in.
After seeing Dad off, I started walking toward the building.
Mom had been up since dawn preparing food, which woke me up early too. The exam consisted of six problems total, split into two sessions of two hours and thirty minutes each. There was, of course, a lunch break in between.
'She didn't have to go to all this trouble...'
The insulated lunchbox in my hand felt a bit embarrassing.
Still, it was packed with delicious stuff, so I was looking forward to lunchtime.
As I walked, I spotted a pond.
"Duck pond?"
What a lazy name.
I approached and saw ducks leisurely floating on the water. I stared blankly for a while.
Kind eyes and broad yellow bills.
Soft, warm feathers and bodies streamlined by fluid dynamics.
Unlike chickens, ducks even shared food with each other.
And that waddling walk was just adorable.
'Even their webbed feet are cute.'
Above all, the fact that this perfect harmony was the result of natural selection was fascinating.
I'd loved ducks ever since my encyclopedia-reading days.
'I wonder if they sell souvenirs.'
I hurried to the shop and found it full of goofy-looking blue plushies.
They grew on me somehow, so I bought some duck merch along with them.
'Gotta give one to Seo-eun.'
"Ah!"
I'd gotten so distracted by the ducks without realizing it.
I could almost hear my teacher's nagging. She'd reminded me several times before the exam.
"Don't expect the graders to understand everything you write. They're scoring over 200 pages of answers—do you think the professors will do it all themselves? Some of the TAs are real airheads, so remember this: When you write your solutions, how should you do it?"
"Explain it simply. In a way anyone can understand."
"Right. Don't just write the answer as it pops into your head and skip the steps!"
She'd lectured me until my ears were numb.
I quickened my pace.
I arrived at the Natural Sciences Building and found the exam room.
I slid the door open.
Inside, there were a lot of familiar faces.
"Yoo Seo-ha! I knew you'd come."
Im Soo-jung noona, sitting quietly in the corner, waved happily.
I felt embarrassed. I ignored her gaze and found my assigned seat from my admission ticket.
"That's the kid, right?"
"Can an elementary kid really compete in the IMO?"
"It happened overseas. I heard Eliya Kronen started at age ten."
The whispers were familiar by now.
I just wanted to grow up fast. Even a few years would do.
A group of students, probably friends, gathered and talked loudly on purpose.
Ah, I remembered reading about this in the encyclopedia.
Social safety nets, conformity pressure, symbolic display.
Forming cliques in unfamiliar places to gain psychological comfort.
Everyone's anxious, huh.
Thinking that way made them seem less obnoxious.
One of the bigger guys pointed at someone and asked,
"Hey! Choi Yoo-jin. Looks like you're not the youngest anymore."
"Hyung! You think I'd be the baby forever?"
His voice was snappy.
I should've spent more time at the souvenir shop.
"Why don't you go say hi? You'll be seeing each other a lot from now on."
"Nah, too much hassle."
I walked over slowly.
People had always pretended not to notice me at other exam halls, so despite the awkwardness, the tests themselves hadn't been affected. But the vibe here was totally different.
'Like an inner circle?'
They clearly felt some camaraderie toward me too.
But why? We'd barely crossed paths, if at all.
"Hey, Yoo Seo-ha!"
Choi Yoo-jin called out to me. No ignoring him now.
"Yeah?"
"You're in fifth grade, right? Where you from?"
What was this, an interrogation?
I felt a surge of defiance, but my body was honest. Big guys scared me.
"Okcheon County, Chungbuk Province."
"No, not that—where'd you go to school!"
He yelled in frustration.
My shoulders hunched.
"Do... Dodam Elementary School?"
That's when he seemed to realize something was off.
"What? You're not from the gifted academy?"
"Nope."
He laughed in disbelief.
"Whoa, this guy's hilarious. You made it here at your age without the gifted academy? Never heard of that before."
"Is that weird?"
"Super weird. All the middle schoolers here went to the same gifted academy. Soo-jung noona over there too."
I had no idea.
I glanced back, and Im Soo-jung noona shrugged.
"Anyway, I'll take good care of you from now on. You got first at the Seoul University math contest, so you'll pass the second round, right? Just stick with me. I'll even let you into our study group—it's a huge help. We don't let just anyone in. I've been the baby of the group till now, but finally someone's under me."
Under you where, exactly?
And when did we meet for you to call yourself hyung?
He'd been radiating "leave me alone" vibes at first, but now he wouldn't shut up.
"Thanks."
I couldn't think of anything else to say, so I bowed politely.
He patted my shoulder, satisfied.
The door slid open.
"Everyone here? Let's start the exam."
The proctors entered, and the room settled down.
A woman in glasses and a scruffy young guy.
An oddly matching pair.
The bell rang, and exam papers were handed out.
Now it was my time alone.
Problem 1.
[In a party of 6 people, prove that there must exist three people who either all know each other or all don't know each other, no matter which three are chosen.]
A classic Ramsey theory problem using the pigeonhole principle.
Scratch, scratch.
The morning problems seemed focused on gauging depth of thought.
'Do they really need two and a half hours?'
Remembering my teacher's advice, I took my time writing detailed, reader-friendly explanations.
"... Therefore, in any case, three people satisfying the condition must exist."
Problem 2.
[Prove that among any 1,000 consecutive natural numbers, there must be at least one composite number.]
A number theory problem.
Seeing it made me chuckle—Seo-eun had lately gotten into number games and memorized every prime under 500. No fun there anymore; next time, I'd start from 1,000 and count down.
Scratch, scratch.
"... Thus, 1001! + k is divisible by k and hence composite. This constructs 1,000 consecutive composites."
Problem 3 was about planetary orbits, like the poster on my wall as a kid.
Closing my eyes, I pictured the beautiful cosmos unfolding.
The elegance of elliptical orbits in polar coordinates. Two foci, yet the sum of distances from any point on the planet to the foci is constant.
The solar system's complex dance governed by such simple math.
A flawless cosmos, without a single error.
How ecstatic must Kepler have been to discover this through calculation?
I wanted to feel that thrill too.
It was meant to stump us, but anyone solid on celestial mechanics would find it straightforward.
Beep—
"Time's up! Submit your answer sheets, then lunch."
As the proctors left, chatter erupted.
"Man, 3 was brutal, right?"
"I bombed starting from 2."
"3's gotta be grad school level, no way."
I quietly picked up my lunchbox and stood.
It was winter—eating outside would suck. Where to go?
Then a voice from behind.
"Hey!"
Im Soo-jung noona?
She called me with her arms crossed, looking pouty.
"Yeah?"
"Eat lunch with me. You don't know anyone else here anyway."
"Thanks."
I meekly followed her.
I didn't know the layout, and there weren't good spots to eat alone nearby.
We ended up at the first-floor cafeteria.
I set my insulated lunchbox on the table.
"Pfft. Kids are kids."
I'd been self-conscious about it already...
She burst out laughing at the colorful character-themed bento.
My face heated up. Next time, I'd give it to my sister.
"My dad used to pack lunches for me at the gifted academy. Miss those days."
She looked wistful.
"What're you having, noona?"
"I'll grab something from over there."
I glanced—the food court had all sorts of options.
As I unpacked my lunch, that group approached. I turned away quick, but they headed straight here.
"Yoo Seo-ha! Why'd you run off? Eat with us."
Thud.
Three of them swarmed, slamming trays around me.
I should've said the seat was taken, but they were already digging in with chopsticks.
"Hey! Why are you guys here again?"
Sure enough, Soo-jung approached from behind, annoyed.
"Come eat with us. The kid's alone. Been a while, Im Soo-jung. How's gifted high school treating you?"
"Whatever!"
They seemed friendly—the big guy offered her the seat next to him. She scowled, dodged it, and sat on my other side instead.
Everyone was starving and started eating.
"This is good."
"Way better than our school cafeteria."
"So, did you solve 3?"
"Our teacher said 1st session 3 and 2nd session 6 aren't for full solves. Just the approach gets high points."
"Same here."
"I think I got it right, though."
The big guy smirked, pulled out his notebook, and jotted the problem.
Then he looked at me.
"Hey, Yoo Seo-ha. You haven't learned this yet, right?"
My dad’s a professor, so he told us—the orbit formula needs celestial and orbital mechanics. That's aerospace engineering stuff..."
He scooted closer, glancing warily at Soo-jung noona.
"Im Soo-jung, did you solve it?"
"Nah. I just wrote assumptions."
"Listen up then. So these six orbital elements..."
"Hold up!"
He was about to explain orbital mechanics after his answer when noona cut him off. She looked at me.
"Yoo Seo-ha, be honest. You solved it, didn't you?"
Why was she putting me on the spot?
But I couldn't lie about solving it.
"Yeah..."
She smirked knowingly and nodded at the big guy's notebook.
"Is that right?"
Messy formulas, faulty derivations.
Couldn't he see his equations' orbits didn't work? They'd crash eventually.
"No. You don't need orbital mechanics for that. Basic astronomy, Newtonian mechanics, and Kepler's laws are enough to derive the answer."
His face flushed at my words.
"You gonna stand by that?"
His tone carried a threat.
I sighed. This was why I didn't want to hang with them...
But I'd started, so no backing down. His attitude grated too.
"Yeah. Let me show you."
I pulled out my notebook and duck pencil.
"First, Kepler's First Law says planetary orbits are ellipses with the sun at one focus."
Scratch, scratch.
"And using Newton's law of universal gravitation and centrifugal force..."
[F = GMm/r² = mv²/r]
"From here, derive the angular velocity and apply Kepler's Third Law to get the relation between semi-major axis and orbital period."
I unfolded the equations step by step.
Suddenly, the table went quiet. Everyone stared at my pen tip.
"Plugging in the problem's conditions..."
The calculation finished with the exact answer.
"Like this."
I set down the pen and looked up to silence.
The big guy gaped at my solution.
The others eyed it skeptically.
"This actually right?"
Couldn't they follow the proof?
"Plug in the numbers and check."
The group fumbled for calculators in their bags.
Click, click, click.
Moments later, their screens matched my notebook exactly.
"It really is..."
An awkward hush fell.
"This is hilarious! Who was teaching who?"
Her high-pitched voice sounded oddly pleased.
Noona grabbed her tray and stood, gesturing for me to follow.
"IMO spots go to me and him, so figure out the rest yourselves."
She dragged me away.
Ah! I hadn't finished Mom's lunch yet.