math-eval/TAL-SCQ5K huggingface dataset:
Problem: About the number 325, five boys said:  Andrei: "This is a 3-digit number"  Boris: "All digits are distinct"  Vick: "The sum of the digits is 10"  Greg: "The unit digits is 5"  Danny: "All digits are odd"  Which of the boys was wrong? 
Options:
aoVal: A
content: Andrei 
aoVal: B
content: Boris 
aoVal: C
content: Vick 
aoVal: D
content: Greg 
aoVal: E
content: Danny 
Answer: E
Analysis: 2 is not odd. 
Knowledge points: Overseas Competition->Knowledge Point->Combinatorics->Logical Reasoning
Source: 其它
Problem: A certain play has two $30$-minute parts and one intermission among them. The play started at $8:00$ and ended at $9:15$. How many minutes long were the intermission? (Adapted from 2010 Math Kangaroo Problem, Level 1-2, Question \#19) 
Options:
aoVal: A
content: $$10$$ 
aoVal: B
content: $$15$$ 
aoVal: C
content: $$20$$ 
aoVal: D
content: $$25$$ 
Answer: B
Analysis: From $8:00$ to $9:15$ = $1$ h $15$ min, $1$ h $15$ min = $75$ min, two $30$-minute parts = $60$ min, $75 - 60$ = $15$ min. 
Knowledge points: Overseas Competition->Knowledge Point->Combinatorics->Time Problem
Source: 其它
Problem: Math workshops start at $5:00$ PM. Today Allan was $15$ minutes late to the workshop. When did Allan come? 
Options:
aoVal: A
content: $5:00$ PM 
aoVal: B
content: $5:05$ PM 
aoVal: C
content: $5:15$ PM 
aoVal: D
content: $5:20$ PM 
Answer: C
Analysis: $15$ minutes past $5:00$ PM is $5:15$ PM. 
Knowledge points: Overseas Competition->Knowledge Point->Combinatorics->Time Problem
Source: 其它
Problem: A school has two classes in the morning, each class continues $$45$$ minutes, and there is a break between classes. The first class starts at $$10:00$$, and the second class ends at $$12:00$$. How long does the courseware rest? 
Options:
aoVal: A
content: $$10$$ 
aoVal: B
content: $$15$$ 
aoVal: C
content: $$20$$ 
aoVal: D
content: $$30$$ 
aoVal: E
content: $$35$$ 
Answer: D
Analysis: From $$10:00$$ to $$12:00$$ = $$2$$ h = $$120$$ min, two $$45$$-minute parts = $$90$$ min, and $$120 - 90 = 30$$ min. 
Knowledge points: Overseas Competition->Knowledge Point->Combinatorics->Time Problem
Source: 其它
Problem: Joseph has $$100$$ mice. Each of them is either white or grey. At least one of the mice is grey, and out of any seven of Joseph\textquotesingle s mice at least four are white. How many grey mice does Joseph have at the most? 
Options:
aoVal: A
content: $$1$$ 
aoVal: B
content: $$3$$ 
aoVal: C
content: $$93$$ 
aoVal: D
content: $$97$$ 
aoVal: E
content: $$99$$ 
Answer: B
Analysis: The maximum is $3$ since any group of $7$ at most $3$ are grey. 
Knowledge points: Overseas Competition->Knowledge Point->Combinatorics->Pigeonhole Principle->Worst Case in Pigeonhole Principle Problems
Problem: Which of the following number is the opposite number of $-5$ 
Options:
aoVal: A
content: $$-5$$ 
aoVal: B
content: $$5$$ 
aoVal: C
content: $\frac{1}{5}$ 
aoVal: D
content: $-\frac{1}{5}$ 
Answer: B
Analysis: Opposite number is the number with opposite sign 
Knowledge points: Overseas Competition->Knowledge Point->Combinatorics->Mathematical Thoughts->Absolute Value
Source: 其它
Problem: Which of the following calculations shows how to work out the number of seconds in~~24 days? 
Options:
aoVal: A
content: 24 x24~ 
aoVal: B
content: 24 x~60 
aoVal: C
content: 24 x~24 x~60 
aoVal: D
content: 24 x~60 x~60 
aoVal: E
content: 24 x~24 x~60 x~60 
Answer: E
Analysis: 1 day = 24 hours，$$1$$ hour = 60 minutes，$$1minute$$ = 60 seconds，$$24$$ days = (24 x 24) hours = [(24x 24) x 60] minutes = 24x 24x 60x 60 seconds 
Knowledge points: Overseas Competition->Knowledge Point->Combinatorics->Time Problem
Source: 其它
Problem: The numbers $$1$$, $$2$$, $$4$$, $$5$$, $$8$$, $$9$$, $$10$$, $$13$$ and $$16$$ are divided into groups of one or more numbers. The sum of the numbers in each group is the same. What is the largest possible number of groups? 
Options:
aoVal: A
content: $$1$$ 
aoVal: B
content: $$2$$ 
aoVal: C
content: $$3$$ 
aoVal: D
content: $$4$$ 
aoVal: E
content: $$5$$ 
Answer: D
Analysis: $1+2+4+5+8+9+10+13+16=68$  $2$ groups: sum of each group is $34$, $34=1+16+2+5+10=4+13+8+9$  $4$ groups: sum of each group is $17$, $17=1+16=2+5+10=4+13=8+9$ 
Knowledge points: Overseas Competition->Knowledge Point->Combinatorics->Combinatorics Involving Extreme Values->Extreme Value with Fixed Sums
Source: 其它
Problem: When calculating $63\times72$ , Judy fails to write the correct column multiplication. She writes one of the four digits as $9$ and gets a result which has a difference of $432$ from the correct one. Which digit does she write incorrectly? 
Options:
aoVal: A
content: $$2$$ 
aoVal: B
content: $$3$$ 
aoVal: C
content: $$6$$ 
aoVal: D
content: $$7$$ 
aoVal: E
content: It\textquotesingle s impossible to determine. 
Answer: B
Analysis: The difference between the wrong answer and the correct one is $432$, whose ones digit is $2$. That means Judy writes neither $2$ nor $3$ wrong.  Compare $7\times63$ and $6\times72$, and we can get the correct answer.  $69\times72-63\times72=432.$ 
Knowledge points: Overseas Competition->Knowledge Point->Combinatorics->Number Puzzles
Source: 其它
Problem: Given that $$2a+3b=84$$, the largest possible value of $$a\times b$$ is~\uline{~~~~~~~~~~}~. 
Options:
aoVal: A
content: $$270$$ 
aoVal: B
content: $$272$$ 
aoVal: C
content: $$294$$ 
aoVal: D
content: $$296$$ 
Answer: C
Analysis: Given that an unchanged sum, the smaller the difference the larger the product. $84=42+42$$$\Rightarrow (2a) \times (3b)=6ab\leqslant {{42}^{2}}\Rightarrow ab\leqslant 294$$. Thus, the largest possible value of $ab$ is $294$. 
Knowledge points: Overseas Competition->Knowledge Point->Combinatorics->Combinatorics Involving Extreme Values->Forming a Maximum/Minimum Multi-Digit Numbers with Fixed Sums
Source: 其它
Problem: There is a cube whose six faces are marked with $3$, $4$, $5$, $6$, $7$, and $8$. If the sum of every two numbers that are on the opposite faces are the same, the number on the opposite face of $4$ is~\uline{~~~~~~~~~~}~ 
Options:
aoVal: A
content: $$3$$ 
aoVal: B
content: $$5$$ 
aoVal: C
content: $$6$$ 
aoVal: D
content: $$7$$ 
aoVal: E
content: $$8$$ 
Answer: D
Analysis: $3+8=4+7=5+6=11$ 
Knowledge points: Overseas Competition->Knowledge Point->Combinatorics->Fun Problems in Math->Fun Math Problems->Dice
Source: 其它
Problem: Bob constructs a rectangular building by many $1\times1\times1$ cubes. The volume of the rectangular building is $210$. What is the least sum of all edges of the rectangular building? 
Options:
aoVal: A
content: $$18$$ 
aoVal: B
content: $$80$$ 
aoVal: C
content: $$72$$ 
aoVal: D
content: $$210$$ 
aoVal: E
content: $$116$$ 
Answer: C
Analysis: Given the product, the smaller the difference, the smaller the sum.  $210=2\times3\times5\times7$, so the length, the width, and the height are $5,$ $6,$ and $7$. $(5+6+7)\times4=72.$ 
Knowledge points: Overseas Competition->Knowledge Point->Combinatorics->Combinatorics Involving Extreme Values->Problems of Extreme Value with Fixed Products
Source: 其它
Problem: Apply this operation to $$(7, 28)$$. What are the last two numbers when the operation stops? 
Options:
aoVal: A
content: $(2,2)$ 
aoVal: B
content: $(3,3)$ 
aoVal: C
content: $(5,5)$ 
aoVal: D
content: $(7,7)$ 
aoVal: E
content: None of the above 
Answer: D
Analysis: D 
Knowledge points: Overseas Competition->Knowledge Point->Combinatorics->Patterns of Figures->Special Changes
Source: 其它
Problem: Lucy, Maria and Anna have a meeting at $$12:30$$. Lucy\textquotesingle s walk takes $$10$$ minutes, Maria\textquotesingle s walk takes a quarter of an hour, and Anna\textquotesingle s walk takes $$40$$ minutes. At what time must the person who needs the longest time to get to the meeting leave her house? 
Options:
aoVal: A
content: $$12:00$$ 
aoVal: B
content: $$12:10$$ 
aoVal: C
content: $$12:15$$ 
aoVal: D
content: $$12:20$$ 
aoVal: E
content: $$11:50$$ 
Answer: E
Analysis: $12:30$ - $40$ min = $11:50$ 
Knowledge points: Overseas Competition->Knowledge Point->Combinatorics->Time Problem->Time Calculation
Source: 其它
Problem: A talk show has two $$30$$-minute parts and has few commercials between them. The TV show started at $$1:50$$ and ended at $$3:00$$. How many minutes long were the commercials in total? 
Options:
aoVal: A
content: $$30$$ min 
aoVal: B
content: $$20$$ min 
aoVal: C
content: $$15$$ min 
aoVal: D
content: $$10$$ min 
Answer: D
Analysis: From $$1:50$$ to $$3:00$$ is $$1$$ h $$10$$ min, and two $$30$$-minute parts = $$60$$ min. $$1$$ hr $$10$$ min = $$70$$ min, and $$70 - 60 = 10$$ min. 
Knowledge points: Overseas Competition->Knowledge Point->Combinatorics->Time Problem
Source: 其它
Problem: Vera leaves home at $$9.15$$ a.m. to walk to Derek's house, which takes her $$25$$ minutes. Carl leaves his house $$5$$ minutes after Vera but only takes $$6$$ minutes to get to Derek's house.  When Carl arrives, how long will he and Derek have to wait for Vera to arrive? 
Options:
aoVal: A
content: $$11$$ min 
aoVal: B
content: $$14$$ min 
aoVal: C
content: $$21$$ min 
aoVal: D
content: $$24$$ min 
Answer: B
Analysis: Vera will arrive at $$9.40$$ a.m.  Carl will leave at $$9.20$$ a.m. and arrive at $$9.26$$ a.m.  So, Carl and Derek will have to wait for $$14$$ min. 
Knowledge points: Overseas Competition->Knowledge Point->Combinatorics->Time Problem
Source: 其它
Problem: The numbers $$1$$, $$5$$, $$8$$, $$9$$, $$10$$, $$12$$, and $$15$$ are divided into groups of one or more numbers. The sum of the numbers in each group is the same. What is the largest possible number of groups? (2016 Math Kangaroo Problem, Level 1-2, Question \#24) 
Options:
aoVal: A
content: $$1$$ 
aoVal: B
content: $$2$$ 
aoVal: C
content: $$3$$ 
aoVal: D
content: $$4$$ 
aoVal: E
content: $$5$$ 
Answer: C
Analysis: $1+5+8+9+10+12+15=60$  $2$ groups: sum of each group is $30$, $30=15+5+10=1+8+9+12$  $3$ groups: sum of each group is $20$, $20=15+5=12+8=10+9+1$  $4$ groups: sum of each group is $15$, $15-12=3$, but there is no $3$ in given numbers  Thus, the largest possible number of groups is $3$. 
Knowledge points: Overseas Competition->Knowledge Point->Combinatorics->Combinatorics Involving Extreme Values->Extreme Value with Fixed Sums
Source: 其它
Problem: Andrea needs an hour to get to the shopping center. If she leaves at $4$ PM, she gets there half an hour after the store closes. If she leaves at $8$ AM, she gets there half an hour before the store opens. What hours is the shopping center open? (2007 Math Kangaroo Problem, Level 1-2, Question \#24) 
Options:
aoVal: A
content: $7:30$ to $4:30$ 
aoVal: B
content: $8:30$ to $5:30$ 
aoVal: C
content: $7:30$ to $5:30$ 
aoVal: D
content: $8:30$ to $4:30$ 
aoVal: E
content: $9:30$ to $4:30$ 
Answer: E
Analysis: If Andrea leaves at $4$ PM, she arrives at the store when it is $5$ PM, and the store closes at $4:30$ PM. If Andrea leaves at $8$ AM, she arrives at the store when it is $9$ AM, and the store opens at $9:30$ AM. 
Knowledge points: Overseas Competition->Knowledge Point->Combinatorics->Time Problem
Source: 其它
Problem: There are two piles of matches, six in one pile and six in the other pile. Andy and Bob take turns to take the matches from any one of the two piles. The number of matches they can take is unlimited, but they have to take at least one each turn. Whoever picks the last match is the winner. If Andy takes the first match,  is guarantee to win. 
Options:
aoVal: A
content: Andy 
aoVal: B
content: Bob 
Answer: B
Analysis: The number of matches in the two piles is the same. No matter how many matches Andy takes from one pile, Bob just needs to take the same amount of matches from the other pile. As long as there are matches for Andy to take, Bob can definitely take away the same amount from the other pile. Therefore, Bob will take away the last match and he is guarantee to win. 
Knowledge points: Overseas Competition->Knowledge Point->Combinatorics->Strategies and Operations->Game Strategy
Problem: All numbers that are divisible by neither $$5$$ nor $$11$$ were removed from a sequence of consecutive natural numbers from $$1$$ to $$5500$$. A new sequence was formed. How many terms are there in this new sequence? (Adapted from $$2004$$ Math Kangaroo Problems, Level $$9-10$$, Question \#$$30$$) 
Options:
aoVal: A
content: $$1000$$ 
aoVal: B
content: $$1500$$ 
aoVal: C
content: $$2500$$ 
aoVal: D
content: $$3300$$ 
aoVal: E
content: $$4400$$ 
Answer: B
Analysis: Method $1$:  $5500\div5=1100$; $5500\div11=500$; $5500\div(5\times11)=100$.  $1100+500-100=1500$.  Method $2$:  In each group formed by $55$ consecutive numbers, $55-(11+5-1)=40$ numbers will be removed.  $5500\div55\times(55-40)=1500$ numbers will remain in this new sequence. 
Knowledge points: Overseas Competition->Knowledge Point->Combinatorics->Strategies and Operations->Operational Problem->Number Operation
Problem: A tortoise is running along a $$5$$ metre track. It can run either half a metre or a metre every second. How many different ways can the tortoise finish the track? 
Options:
aoVal: A
content: $$72$$ 
aoVal: B
content: $$89$$ 
aoVal: C
content: $$91$$ 
aoVal: D
content: $$56$$ 
Answer: B
Analysis: $$1$$,$$2$$,$$3$$,$$5$$,$$8$$,$$13$$,$$21$$,$$34$$,$$55$$,$$89$$ 
Knowledge points: Overseas Competition->Knowledge Point->Combinatorics->Strategies and Operations->Inductive Recursion
Problem: A cat divides $$24$$ cans of tuna into $$4$$ groups. Each group has at least $$1$$ can of tuna, and the number of cans in each group \uline{cannot be the same}. There are at mostcans of tuna in the group that has the largest number of cans. 
Options:
aoVal: A
content: $$6$$ 
aoVal: B
content: $$18$$ 
aoVal: C
content: $$21$$ 
aoVal: D
content: $$24$$ 
Answer: B
Analysis: $$ 1 + 2+3 + 18 = 24$$ 
Knowledge points: Overseas Competition->Knowledge Point->Combinatorics->Number Puzzles->Number Puzzles (sign of operations)->Obtaining Maximum/Minimum Values
Problem: Basil has several domino tiles, as shown in the figure. He wants to arrange them in a line according to the well-known "domino rules": in any two tiles that are next to each other, the squares that touch must have the same number of points. What is the largest number of tiles he can arrange in this way?  [insert picccc] 
Options:
aoVal: A
content: $$3$$ 
aoVal: B
content: $$4$$ 
aoVal: C
content: $$5$$ 
aoVal: D
content: $$6$$ 
aoVal: E
content: $$7$$ 
Answer: C
Analysis: One possible configuration for 5 dominoes is shown.  [pic] 
Knowledge points: Overseas Competition->Knowledge Point->Combinatorics->Logical Reasoning
Source: 其它
Problem: A school has three classes in the morning, and there is a $$15$$-minutes break between each two classes. Each class is of the same length. The first class starts at $$9:45 $$, and the third class ends at $$12:00 $$. How long is each class? 
Options:
aoVal: A
content: $$25$$ 
aoVal: B
content: $$30$$ 
aoVal: C
content: $$35$$ 
aoVal: D
content: $$40$$ 
aoVal: E
content: $$45$$ 
Answer: C
Analysis: From $$9:45$$ to $$12:00$$ = $$2$$ h $$15$$m = $$135$$ min, two $$15$$-minute parts = $$30$$ min, and $$135 - 30 = 105$$ min. $$105\div3=35$$min 
Knowledge points: Overseas Competition->Knowledge Point->Combinatorics->Time Problem
Source: 其它
Problem: The weights of four boys are 45kg, 48kg, 52kg and 53kg. Mason\textquotesingle s weight is an even number. Joshua\textquotesingle s weight is a multiple of 5. Christopher is not the heaviest and Mateo is not the lightest. Who is the heaviest among the four boys? 
Options:
aoVal: A
content: Mason 
aoVal: B
content: Joshua 
aoVal: C
content: Christopher 
aoVal: D
content: Mateo 
aoVal: E
content: Impossible to determine 
Answer: D
Analysis: Mason\textquotesingle s weight is an even number = 48kg / 52kg.  Joshua\textquotesingle s weight is a multiple of 5 = 45kg.  Christopher is not the heaviest = x 53kg.  Mateo is not the lightest = x 45kg  Jason - \textgreater{} either Mason or Christpoher is 28/52kg -\textgreater{} Mateo. 
Knowledge points: Overseas Competition->Knowledge Point->Combinatorics->Logical Reasoning
Source: 其它
Problem: From $1$ to $45$, how many numbers must be chosen at least to ensure that there are two of chosen numbers sum to $30$? 
Options:
aoVal: A
content: $$25$$ 
aoVal: B
content: $$30$$ 
aoVal: C
content: $$31$$ 
aoVal: D
content: $$32$$ 
aoVal: E
content: $$22$$ 
Answer: D
Analysis: $$16+1+14+1=32$$ 
Knowledge points: Overseas Competition->Knowledge Point->Combinatorics->Constructing and Proving
Source: 其它
Problem: Teacher James distributes $82$ apples to $12$ students. At least how many apples can the student with the most apples get? 
Options:
aoVal: A
content: $$5$$ 
aoVal: B
content: $$6$$ 
aoVal: C
content: $$7$$ 
aoVal: D
content: $$8$$ 
aoVal: E
content: $$9$$ 
Answer: C
Analysis: $82\div12=6R10$, $6+1=7$. 
Knowledge points: Overseas Competition->Knowledge Point->Combinatorics->Pigeonhole Principle
Source: 其它
Problem: $A$ and $B$ play a game as follows. First $A$ says $1, 2$ or $3$. Then $B$ can add $1, 2$ or $3$ to the number the first player said. The game continues with the players playing alternately, in each turn adding $1, 2$ or $3$ to the previous number. For example, A can say $2$, then B can say $5$, then A could say $6$, and so on. The player who says $100$ wins. Who has the winning strategy? 
Options:
aoVal: A
content: A 
aoVal: B
content: B 
Answer: B
Analysis: Observe that B can always say a multiple of 4 in his turn. For example, consider the following sequence of moves: A-1; B-4; A-6; B-8 and so on. Regardless of what A says, B can always say a multiple of 4. Hence B will say 100 and will win 
Knowledge points: Overseas Competition->Knowledge Point->Combinatorics->Strategies and Operations
Source: 其它
Problem: SASMO 2016 P2 Q7  It takes 5 mintues to boil an egg. What is the least amount of time it takes to boil 3 eggs? 
Options:
aoVal: A
content: $$8$$minutes 
aoVal: B
content: $$12$$minutes 
aoVal: C
content: $$15$$minutes 
aoVal: D
content: $$18$$minutes 
aoVal: E
content: None of the above 
Answer: E
Analysis: 5 minutes, boil together. 
Knowledge points: Overseas Competition->Knowledge Point->Combinatorics->Time Problem
Source: 其它
Problem: There are $9$ water glasses, all facing up. You need to turn exactly $2$ glasses over in each time. Is it possible to turn all $9$ of them upside down after several moves? 
Options:
aoVal: A
content: Yes, it is possible. 
aoVal: B
content: No, it is impossible. 
aoVal: C
content: I have no idea. 
Answer: B
Analysis: You have to flip a cup an odd number of times to turn it over.  To make all the $9$ cups face down, you have to make an odd number of flips.  Each time you flip exactly $2$ cups, the total number of flips is an even number of times.  Hence it is impossible. 
Knowledge points: Overseas Competition->Knowledge Point->Combinatorics->Strategies and Operations->Operational Problem->Turning Mugs over
Problem: David went to watch $Spider Man$ at the cinema on June $25$\textsuperscript{th}. The movie started at $6 : 32$ P.M. and finished at $7 : 54$ P.M.. On the same day, Mary needed to go abroad by plane. The plane took off at $11 : 40$ P.M., and the time she spent on plane was $2$ hours and $11$ minutes longer than that David spent at the cinema. When would Mary get off the plane? 
Options:
aoVal: A
content: $3 : 23$ P.M. on June $25$\textsuperscript{th} 
aoVal: B
content: $3 : 13$ A.M. on June $25$\textsuperscript{th} 
aoVal: C
content: $3 : 13$ P.M. on June $26$\textsuperscript{th} 
aoVal: D
content: $3 : 13$ A.M. on June $26$\textsuperscript{th} 
aoVal: E
content: $3 : 23$ A.M. on June $26$\textsuperscript{th} 
Answer: D
Analysis: From $6 : 32$ P.M. to $7 : 54$ P.M., it lasted $1$ hour and $22$ minutes.  The time Mary spent on plane: $1$ hour and $22$ minutes $+$ $2$ hours and $11$ minutes $=$ $3$ hours and $33$ minutes.  Thus, Mary would get off the plane at $3 : 13$ A.M. on June 26\textsuperscript{th}. 
Knowledge points: Overseas Competition->Knowledge Point->Combinatorics->Time Problem->Time Calculation
Source: 其它
Problem: Cindy and Chloe are siblings. Each of them have $$2$$ brothers and $$2$$ sister in. How many children are there in the family? 
Options:
aoVal: A
content: $$4$$ 
aoVal: B
content: $$5$$ 
aoVal: C
content: $$6$$ 
aoVal: D
content: $$8$$ 
aoVal: E
content: $$10$$ 
Answer: B
Analysis: Cindy is sister to Chloe and Chloe is sister to Cindy. Thus, they have one more common sister. There are a total of $$3$$ girls in the family.  Their brother are the same, thus $$2$$ boys in the family.  In total $$5$$ children. 
Knowledge points: Overseas Competition->Knowledge Point->Combinatorics->Logical Reasoning
Source: 其它
Problem: Jacky wants to insert the digit 3 somehwere in the number 2014. Where should she insert digit 3 if she wants her five digit number to be as small as possible? 
Options:
aoVal: A
content: in front of 2014 
aoVal: B
content: between the 2 and the 0 
aoVal: C
content: between the 0 and the 1 
aoVal: D
content: between the 1 and the 4 
aoVal: E
content: behind 2014. 
Answer: D
Analysis: 3 is a digit between 1 and 4.  Try to put into and see which number is the smallest. 
Knowledge points: Overseas Competition->Knowledge Point->Combinatorics->Combinatorics Involving Extreme Values->Forming a Maximum/Minimum Multi-Digit Numbers with Fixed Sums
Source: 其它
Problem: Jack, Rebecca, Dustin and Steve write down one number, respectively, which are $44$, $85$, $72$ and $39$.Both Jack\textquotesingle s and Dustin\textquotesingle s numbers are odd. Both Jack\textquotesingle s and Steve\textquotesingle s numbers are more than $60$. What number is written by Rebecca? 
Options:
aoVal: A
content: $$44$$ 
aoVal: B
content: $$85$$ 
aoVal: C
content: $$72$$ 
aoVal: D
content: $$39$$ 
aoVal: E
content: Impossible to determine 
Answer: A
Analysis: Eliminate odd numbers and numbers more than $60$, so the only number left is $44$. 
Knowledge points: Overseas Competition->Knowledge Point->Combinatorics->Logical Reasoning
Source: 其它
Problem: In class, Anna, Bell, and Julie are doing math homework at school. Among them, Anna took $$18$$ minutes and $$25$$ seconds. Bell took $$19$$ minutes and $$36$$ seconds, and Julie took $$20$$ minutes and $$15$$ seconds. How long did the three take in total? (adapted from 2008 Math Kangaroo Problem, Level 3 - 4, Question \#15) 
Options:
aoVal: A
content: $$57$$ minutes $$16$$ seconds 
aoVal: B
content: $$58$$ minutes $$16$$ seconds 
aoVal: C
content: $$58$$ minutes $$26$$ seconds 
aoVal: D
content: $$58$$ minutes $$6$$ seconds 
aoVal: E
content: $$57$$ minutes $$26$$ seconds 
Answer: B
Analysis: $18$ minutes + $19$ minutes + $20$ minutes + $25$ seconds $+$ $36$ seconds + $15$ seconds = $57$ minutes $76$ seconds = $58$ minutes $16$ seconds 
Knowledge points: Overseas Competition->Knowledge Point->Combinatorics->Time Problem->Time Calculation
Problem: The time in Thornsburg is $$6$$ hours ahead of London. The time in London is $$8.27$$ pm. What is the time in Thornsburg?  Choose the answer. 
Options:
aoVal: A
content: $$02.27$$ pm 
aoVal: B
content: $$14.27$$ pm 
aoVal: C
content: $$02.27$$ pm 
aoVal: D
content: $$02.27$$ am 
aoVal: E
content: $$14.27$$ am 
Answer: D
Analysis: $6$ hours ahead of $08:27$ pm is $02:27$ am. 
Knowledge points: Overseas Competition->Knowledge Point->Combinatorics->Time Problem->Time Calculation