Olympiad: time and calendar puzzles ★★★

Tests: 2 of 11 right · Exam: 1 of 4 right · Kind: ★★★ · Understood: 7 of 15 · Run: 2026-10-18, commit f3c23ea72

Lesson 192 of the world course of Mova's primary school, as Mova's small model took its tests: it had read this lesson and the ones before it and learned from their exercises. Each test shows the options in the order the student saw them, its choice, the right answer, the score of every option and why it chose. The lesson itself, sentence by sentence with trees and pragmatics: the lesson in the corpora.

Every question of this lesson and each of its options parsed by Mova, with trees and pragmatics: the lesson's questions in the corpora.

Test 1 · ★★★ · right ✓

Mia: "my bday was on a Wednesday this year and there's no 29 Feb before the next one, so it's a Wednesday every year innit." What is true?

1. It moves on a whole week to the next Wednesday — score 3
2. Next year it moves on one day, to a Thursday — ← Mova's choice · ✓ the right answer · score 5
3. It jumps back to a Tuesday — no support
4. It stays on a Wednesday for good, as long as no 29 February comes — score 1

Why: It took the question to ask which statement is true. It chose option 2 with score 5, against 3 for the next best. Its support: lesson 115, line 3: «A normal year is 52 weeks and 1 day, so a date moves on one weekday each year; if a 29 February comes in between, it moves on two. A birthday on a Wednesday th…», reached through the same lesson line as the sentence the question matched. What matched: the same action «move» (+4); the same property (+1). · the question and its options parsed, with trees and pragmatics

Test 2 · ★★★ · wrong ✗

Nan: "I've told you a million times, the bus goes at 8:40! It's 8:25 — no, my watch is slow, it's 8:28." How long until the bus?

1. 15 minutes — ← Mova's choice · no support
2. 12 minutes — ✓ the right answer · no support
3. 8 minutes and 40 seconds — no support
4. A million minutes, near enough — no support

Why: No option found support in what it remembers, so it guessed: it took the first option shown. · the question and its options parsed, with trees and pragmatics

Test 3 · ★★★ · wrong ✗

Jack, at the servo: "Waited literally forever for the car wash, like three hours. Well, 25 minutes tbh." He started waiting at 2:50. When did it end?

1. At 3:05, twenty-five minutes before — ← Mova's choice · no support
2. At 3:15 — ✓ the right answer · no support
3. At 5:50, three hours later — no support
4. At 3:25 — no support

Why: No option found support in what it remembers, so it guessed: it took the first option shown. · the question and its options parsed, with trees and pragmatics

Test 4 · ★★★ · wrong ✗

Leo: "The clock did 6 bongs in 5 seconds, so 12 bongs is 10 seconds, easy." What has he missed?

1. Counting gaps: 6 bongs make 5 gaps, 12 make 11, so 11 seconds — ✓ the right answer · score 2
2. Bongs take longer than gaps, so 12 bongs must take 12 seconds — score 2
3. Nothing: 6 bongs in 5 seconds means 12 bongs in 10 — no support
4. Clocks always strike faster at noon, so 12 bongs is quicker — ← Mova's choice · score 4

Why: It took the question to ask what it is done to. It chose option 4 with score 4, against 2 for the next best. Its support: lesson 192, line 8: «A clock striking 6 makes 5 gaps between its bongs; if that takes 5 seconds, each gap is 1 second, so striking 12, with 11 gaps, takes 11 seconds.», reached through a sentence linked to the one the question matched. What matched: the same action «strike» (+2); the same doer «clock» (+2). The right option, 1, scored 2. · the question and its options parsed, with trees and pragmatics

Test 5 · ★★★ · right ✓

Zoe: "No cap, 2000 was the first year of the 21st century, everyone partied." What is right?

1. The century began in 1999 — score 7
2. Centuries start with whatever year people pick — score 7
3. She's right, 2000 opened the century — score 2
4. The partying is true, but the century began in 2001 — ← Mova's choice · ✓ the right answer · score 9

Why: It took the question to ask which statement is true. It chose option 4 with score 9, against 7 for the next best. Its support: lesson 192, line 4: «Calendars have their own traps too: 2100 will skip 29 February, the 21st century began in 2001, not 2000, and from 10 BC to AD 10 is 19 years, because no year…», reached through the same lesson line as the sentence the question matched. What matched: the same action «begin» (+4); the same doer «21st century» (+3); the same place «2001» (+2). · the question and its options parsed, with trees and pragmatics

Test 6 · ★★★ · wrong ✗

Rhys from Cardiff, tamping: "Clocks went forward and I lost my sleep! Bed at 10, alarm at 7, that's 9 hours, so why am I knackered?" What is the real answer?

1. He slept 10 hours, because the clocks went back that night — ← Mova's choice · score 6
2. He slept 7 hours, because he lost two hours that night — no support
3. He slept only 8 hours, because an hour was skipped — ✓ the right answer · no support
4. He slept 9 hours and is only pretending to be tired — no support

Why: It took the question to ask why something happens (its cause). It chose option 1 with score 6, the only option with support. Its support: lesson 121, line 13: «The night the clocks go back has 25 hours, and the night they go forward has 23.», reached through the same lesson line as the sentence the question matched. What matched: the same action «go back» (+4); the same doer «clocks» (+2). The right option, 3, found no support in what it remembers. · the question and its options parsed, with trees and pragmatics

Test 7 · ★★★ · wrong ✗

Kaylee from Texas: "Y'all, I'm fixin' to call Grandma in Kyiv at 9 in the morning New York time, in January. Will she be up?" What is true?

1. Yes, it is 9 am for everyone everywhere at once — ← Mova's choice · no support
2. No; it is 9 pm the night before in Kyiv — no support
3. No; it is 2 am in Kyiv and she is fast asleep — no support
4. Yes; it is 4 pm in Kyiv, the middle of the afternoon — ✓ the right answer · no support

Why: No option found support in what it remembers, so it guessed: it took the first option shown. · the question and its options parsed, with trees and pragmatics

Test 8 · ★★★ · wrong ✗

Sam, in 2026: "My cousin was born on 29 February 2016. She's only 2 lol, she's had two birthdays." What is wrong?

1. She is 2 at school and 10 only at home — no support
2. She is 8, because 2016 had no 29 February — no support
3. Nothing; leaplings get one year older every 4 years — ← Mova's choice · score 4
4. She is 10; she has had only 2 real 29 February birthdays — ✓ the right answer · no support

Why: It took the question to ask which statement is true. It chose option 3 with score 4, the only option with support. Its support: lesson 112, line 4: «People born on 29 February, called leaplings, have their real birthday date only once every 4 years, but they still grow one year older every year. Olivia, bor…», reached through the same lesson line as the sentence the question matched. What matched: the same doer «leaplings» (+3); the same property (+1). The right option, 4, found no support in what it remembers. · the question and its options parsed, with trees and pragmatics

Test 9 · ★★★ · wrong ✗

In a cartoon an explorer digs up a coin stamped "25 BC" and shouts, "Priceless!" Why is the expert laughing?

1. 25 BC is after AD 1, so the date is impossible — ← Mova's choice · no support
2. Coins from that time are worth very little — no support
3. Coins were never made before AD 1, as the Romans had none — no support
4. Nobody in 25 BC knew to count years "BC", so it is a fake — ✓ the right answer · no support

Why: No option found support in what it remembers, so it guessed: it took the first option shown. · the question and its options parsed, with trees and pragmatics

Test 10 · ★★★ · wrong ✗

Callum from Glasgow: "It's dreich and the clouds are thick, but the sundial in the park'll tell us the time, aye?" What is true?

1. Yes; sundials work in any weather — ← Mova's choice · score 3
2. No; with no sunshine there is no shadow to read — ✓ the right answer · no support
3. No; sundials only work at night — score 3
4. Yes, but only if he shines a torch at the stone — no support

Why: It took the question to ask which statement is true. It chose option 1 with score 3, tied with another option at 3 (the first shown, or the one claiming less beyond what it knows, wins). Its support: lesson 192, line 17: «A sundial works only when the Sun casts a shadow, so it is no use at night or on a grey, cloudy day.», reached through the option's own match among the sentences about the question's things. What matched: the same action «work» (+3). The right option, 2, found no support in what it remembers. · the question and its options parsed, with trees and pragmatics

Test 11 · ★★★ · wrong ✗

Mia: "I'm 9 and my brother's 3, so I'm 3 times his age. In 3 years I'll still be 3 times as old, obvs." Is she right?

1. Yes; 3 times as old stays the same for life — ← Mova's choice · score 7
2. No; she'll be 12 and he'll be 6, only twice as old — ✓ the right answer · no support
3. Yes; she'll be 18 and he'll be 6 — no support
4. No; they will be the same age — no support

Why: It took the question to ask which statement is true. It chose option 1 with score 7, the only option with support. Its support: lesson 183, line 16: «The gap between two people's ages stays the same: when a 5-year-old reaches 10, his brother who is 5 years older is 15.», reached through a sentence linked to the one the question matched. What matched: the same action «stay» (+4); the same property (+2); a different doer (counts against) (+1). The right option, 2, found no support in what it remembers. · the question and its options parsed, with trees and pragmatics

Exam question 1 · formal language · wrong ✗

It is given that the present day is a Wednesday. Ascertain the day of the week which shall fall one hundred days hence.

1. Thursday — ← Mova's choice · no support
2. Saturday — no support
3. Friday — ✓ the right answer · no support
4. Wednesday — no support

Why: No option found support in what it remembers, so it guessed: it took the first option shown. · the question and its options parsed, with trees and pragmatics

Exam question 2 · formal language · wrong ✗

A clock occupies five seconds in striking six, the intervals between strokes being equal. Determine the time it occupies in striking twelve.

1. Fourteen seconds — ← Mova's choice · no support
2. Eleven seconds — ✓ the right answer · no support
3. Twelve seconds — no support
4. Ten seconds — no support

Why: No option found support in what it remembers, so it guessed: it took the first option shown. · the question and its options parsed, with trees and pragmatics

Exam question 3 · formal language · right ✓

A person born in the year 20 BC attains a birthday in AD 20. State the age then attained, there being no year zero.

1. Thirty-nine — ← Mova's choice · ✓ the right answer · no support
2. Twenty — no support
3. Forty — no support
4. Forty-one — no support

Why: No option found support in what it remembers, so it guessed: it took the first option shown. · the question and its options parsed, with trees and pragmatics

Exam question 4 · formal language · wrong ✗

Identify which of the following years shall contain no twenty-ninth day of February.

1. 2028 — ← Mova's choice · no support
2. 2032 — no support
3. 2400 — no support
4. 2100 — ✓ the right answer · no support

Why: No option found support in what it remembers, so it guessed: it took the first option shown. · the question and its options parsed, with trees and pragmatics

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