math-eval/TAL-SCQ5K huggingface dataset:
Problem: My sister runs $$10\text{km}$$ per hour, and I run $$2\text{km}$$ in $$15$$ minutes. If we both run for $$2$$ hours, my sister will run$$\text{km}$$ farther than I will. 
Options:
aoVal: A
content: $$2$$ 
aoVal: B
content: $$4$$ 
aoVal: C
content: $$6$$ 
aoVal: D
content: $$8$$ 
Answer: B
Analysis: I run $$2\text{km}$$ in $$15$$ minutes, or $$8\text{km}$$ in $$1$$ hour. In $$2$$ hours, I will run $$16\text{km}$$ and my sister will run $$20\text{km}$$. She will run $$4\text{km}$$ farther than I will. 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules
Problem: In 2010 about 120 million digital still cameras were sold worldwide.  By 2018 this number had decreased by 85\%.  About how many million digital still cameras were sold in 2018? 
Options:
aoVal: A
content: $$18$$ 
aoVal: B
content: $$28$$ 
aoVal: C
content: $$38$$ 
aoVal: D
content: $$48$$ 
aoVal: E
content: $$58$$ 
Answer: A
Analysis: $120\times（1-85\textbackslash\%）=18$ 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Solving Problems Involving Fractions and Percentages->Knowing the Base
Source: 其它
Problem: Monica arrived in the Kangaroo Camp on July 25th in the morning and left the camp on August 3rd in the afternoon. How many nights did she sleep in the camp? 
Options:
aoVal: A
content: $$7$$ 
aoVal: B
content: $$9$$ 
aoVal: C
content: $$10$$ 
aoVal: D
content: $$30$$ 
aoVal: E
content: $$8$$ 
Answer: B
Analysis: July has 31 days. She arrive on morning of July 25.  From July 25 to 31, there are 7 nights that she slept in the camp.  Then she slepft for 2 days in August, since she left on the afternoon Aug 3 already.  Hence, 2=7=9 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Periodic Problems->Periodic Problems of Time->Period of Dates
Source: 其它
Problem: There are three books Chinese, Math, and English. Sissy wants to put them in the bookcase. How many ways are there for the three books to put? List out all the ways. 
Options:
aoVal: A
content: $$6$$ 
aoVal: B
content: $$5$$ 
aoVal: C
content: $$4$$ 
aoVal: D
content: $$3$$ 
Answer: A
Analysis: List out all the possible ways in order.  $C A E$  $C E A$  $A C E$  $A E C$  $E C A$  $E A C $ 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules
Source: 其它
Problem: In a fruit stall, there are 25 apples. There are 9 fewer apples than oranges. How many oranges are there in the fruit stall? 
Options:
aoVal: A
content: $$17$$ 
aoVal: B
content: $$16$$ 
aoVal: C
content: $$34$$ 
aoVal: D
content: $$15$$ 
Answer: C
Analysis: $$25+9=34$$ 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules
Problem: Chloe has＄$$7$$. She is going to buy $$6$$ pens, and each costs $90$ cents. She also buys a certain number of pencils, and each costs $$50$$ cents. How many pencils at most can she buy? (Adapted from 2007 Math Kangaroo Problem, Level 3-4, Question \#4) 
Options:
aoVal: A
content: $$5$$ 
aoVal: B
content: $$4$$ 
aoVal: C
content: $$3$$ 
aoVal: D
content: $$2$$ 
aoVal: E
content: $$1$$ 
Answer: C
Analysis: $7$ dollars =~ $700$ cents  $(700-6\times90)\div50=3R10$ 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Unitary Method Problems->Finding the Total Value using Unitary Method
Problem: Isabella must take four $100$-point tests in her math class. Her goal is to achieve an average grade of $95$ on the tests. Her first two test scores were $97$ and $91$. After seeing her score on the third test, she realized she can still reach her goal. What is the lowest possible score she would have made on the third test? 
Options:
aoVal: A
content: $$90$$ 
aoVal: B
content: $$92$$ 
aoVal: C
content: $$95$$ 
aoVal: D
content: $$96$$ 
aoVal: E
content: $$97$$ 
Answer: B
Analysis: Isabella wants an average grade of $95$ on her $4$ test; this also means that she wants the sum of her test scores to be at least $95\times 4=380$ (if she goes over this number, she\textquotesingle ll be over the goal!). She\textquotesingle s already taken two tests, which sum to $97+91=188$, which means she needs $380-188=192$ more points to achieve her desired average. In order to minimize the score on the third test, we assume that Isabella will receive all $100$ points on the fourth test. Therefore, the lowest score on the third test would be $192-100=92$. 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Average Problems 
Source: 其它
Problem: \textbf{In the setting of the previous problem, about what percent of the variation in the number of service calls is explained by the linear relation between number of service calls and number of machines?~} 
Options:
aoVal: A
content: 86\% 
aoVal: B
content: 93\% 
aoVal: C
content: 74\% 
aoVal: D
content: None of the above 
aoVal: E
content: \textbf{Can't tell from the information given} 
Answer: C
Analysis: $$R^{2} = r^{2} = 0.86^{2} = 0.7396$$ 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules
Source: 其它
Problem: Otto the octopus needs $$2$$ tentacles to juggle up to $$3$$ balls.  If Otto uses all $$8$$ tentacles, Otto can juggle up to  balls. 
Options:
aoVal: A
content: $$8$$ 
aoVal: B
content: $$9$$ 
aoVal: C
content: $$12$$ 
aoVal: D
content: $$24$$ 
Answer: C
Analysis: Otto needs $$2$$ tentacles to juggle up to $$3$$ balls. Using $$8=4\times2$$ tentacles, Otto can juggle up to $$4\times3 = 12$$ balls. 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Unitary Method Problems->Applying Multiplication and Division
Problem: Lucy was $$20$$ years old when Bill was $$12$$. Now, Bill is $$17$$ years old. How old is Lucy? 
Options:
aoVal: A
content: $$12$$ 
aoVal: B
content: $$13$$ 
aoVal: C
content: $$21$$ 
aoVal: D
content: $$23$$ 
aoVal: E
content: $$25$$ 
Answer: E
Analysis: The age difference between Lucy and Bill is $$20~-- 12 = 8$$, which will not change. Thus, Lucy is $$17 + 8 = 25$$ years old. 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules
Source: 其它
Problem: Olivia has $32$ clothes, $4$ of them are yellow, $10$ are blue, $13$ are purple, and the others are white. Suddenly the power is off, and it is all black in the room. At least how many clothes should Olivia pick in order to guarantee that she gets $8$ clothes in the same color? 
Options:
aoVal: A
content: $$8$$ 
aoVal: B
content: $$12$$ 
aoVal: C
content: $$17$$ 
aoVal: D
content: $$24$$ 
aoVal: E
content: $$32$$ 
Answer: D
Analysis: $$4+5+7+7+1=24$$ 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules
Problem: Jack mixed $20$ grams of sugar with $30$ grams of water. What is the percent concentration of the sugar solution? Then Jack added $50$ grams of water. What is the percent concentration the sugar solution? 
Options:
aoVal: A
content: $$40 \textbackslash\% $$; $$20\textbackslash\% $$. 
aoVal: B
content: $$40 \textbackslash\% $$; $$25 \textbackslash\% $$. 
aoVal: C
content: $$50 \textbackslash\% $$; $$20 \textbackslash\% $$. 
aoVal: D
content: $$50 \textbackslash\% $$;~$$25 \textbackslash\% $$. 
Answer: A
Analysis: $n\_1=\frac{20}{20+30}\times100\textbackslash\%=40\textbackslash\%$;  $n\_2=\frac{20}{20+30+50}\times100\textbackslash\%=20\textbackslash\%$. 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Concentration Problems->Basic Concentration Problems->Calculating Solvent from Solution and Solute
Problem: Colin has $$70$$ stamps. He has $$7$$ times as many stamps as Ben. How many more stamps does Colin have than Ben? 
Options:
aoVal: A
content: $$73$$ 
aoVal: B
content: $$70$$ 
aoVal: C
content: $$60$$ 
aoVal: D
content: $$10$$ 
Answer: C
Analysis: $$70 \div10 = 7$$  $$70-10=60$$ 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Unitary Method Problems
Problem: In a certain year, June $$24$$\textsuperscript{th}~is Thursday. What day is August $$27$$\textsuperscript{th~}in this year?  $\textasciitilde$ 
Options:
aoVal: A
content: Monday 
aoVal: B
content: Tuesday 
aoVal: C
content: Thursday 
aoVal: D
content: Friday 
aoVal: E
content: Saturday 
Answer: D
Analysis: Counting from June $$24$$\textsuperscript{th}, after $30-24=6$ days it is June $$30$$\textsuperscript{st}. After $58$ days it is August $$27$$\textsuperscript{th}. In total, there are $6+58=64$ days. $64\div 7 =9R1$, which means August $$27$$\textsuperscript{th~}is Friday. 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Periodic Problems->Periodic Problems of Time
Problem: A tank filled with 200 litres of water weighs 350kg. The same tank filled with 150 litres of water weighs 315kg. What is the weight of the empty tank? 
Options:
aoVal: A
content: $$120$$kg 
aoVal: B
content: $$150$$kg 
aoVal: C
content: $$165$$kg 
aoVal: D
content: $$210$$kg 
aoVal: E
content: None of the above 
Answer: D
Analysis: T + 200L = 350kg $\cdots $ ①  -) T + 150L = 315kg $\cdots $ ②  \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_  (50L = 35kg) x3 = 150L = 105kg  315kg - 105kg = 210kg 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Applying Addition and Subtraction
Source: 其它
Problem: Esther made $$8$$ paper stars.  Faiza made $$4$$ times as many paper stars as Esther did.  Gurmit made $$5$$ times as many paper stars as Esther did,  How many paper stars did the three boys make altogether? 
Options:
aoVal: A
content: $$64$$ 
aoVal: B
content: $$80$$ 
aoVal: C
content: $$144$$ 
aoVal: D
content: $$152$$ 
Answer: B
Analysis: omitted 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Questions Involving Sum, Difference and Multiples->Basic Computation of the Multiples
Problem: Debbie bought a loaf of bread for $$$4$$.  She paid for the bread with a $$$10$$ note.  How much change did Debbie receive? ． 
Options:
aoVal: A
content: $$$4$$ 
aoVal: B
content: $$$6$$ 
aoVal: C
content: $$$14$$ 
aoVal: D
content: $$$40$$ 
Answer: B
Analysis: $$10-4=6$$ 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Applying Addition and Subtraction->Simple Addition and Subtraction
Problem: Six rectangles each with a common base width of $2$ have lengths of $1,4,9,16,25$, and 36 . What is the sum of the areas of the six rectangles? (2014 AMC 8, Question \#6) 
Options:
aoVal: A
content: $$91$$ 
aoVal: B
content: $$93$$ 
aoVal: C
content: $$162$$ 
aoVal: D
content: $$182$$ 
aoVal: E
content: $$202$$ 
Answer: D
Analysis: The sum of the areas is equal to $2 \cdot 1+2 \cdot 4+2 \cdot 9+2 \cdot 16+2 \cdot 25+2 \cdot 36$. This is equal to $2(1+4+9+16+25+36)$, which is equal to $2 \cdot 91$. This is equal to our final answer of (D) 182 . 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Interval Problems
Source: 其它
Problem: My old printer printed $$13$$ pages in $$3$$ seconds. My new printer prints $$21$$ pages in $$2$$ seconds. In $$6$$ seconds my new printer printsmore pages than my old one could have. 
Options:
aoVal: A
content: $$8$$ 
aoVal: B
content: $$16$$ 
aoVal: C
content: $$27$$ 
aoVal: D
content: $$37$$ 
Answer: D
Analysis: My old printer printed $$13$$ pages in $$3$$ seconds or $$26$$ pages in $$6$$ seconds. My new printer prints $$21$$ pages in $$2$$ seconds or $$63$$ pages in $$6$$ seconds. The difference is $$63 - 26=37$$. 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Applying Addition and Subtraction->Simple Addition and Subtraction
Problem: March $$12$$th, $$2012$$ was a Monday. What day was May $$1$$st, $$2015$$? 
Options:
aoVal: A
content: Tuesday 
aoVal: B
content: Wednesday 
aoVal: C
content: Thursday 
aoVal: D
content: Friday 
Answer: D
Analysis: March $$12$$th, $$2013$$: Tuesday  March $$12$$th, $$2014$$: Wednesday  March $$12$$th, $$2014$$: Thursday  $(31-12)+30+1=50$, $50\div 7=7\textbackslash{} \rm r \textasciitilde1$, so it was Friday. 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Periodic Problems->Periodic Problems of Time->Period of Dates
Problem: SASMO 2014 P2 Q10  Tim is 8 years old and Sally is 4 years old. How old will Sally be when Tim is 14 years old? 
Options:
aoVal: A
content: $$7$$ 
aoVal: B
content: $$8$$ 
aoVal: C
content: $$9$$ 
aoVal: D
content: $$10$$ 
aoVal: E
content: None of the above 
Answer: D
Analysis: 8 + 6 = 14  4 + 6 = 10 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Age Problems
Source: 其它
Problem: Pip is 10 years and 2 months old. Bud is 124 months old. Bob has been alive for 3660 days. Who is the oldest? 
Options:
aoVal: A
content: Pip 
aoVal: B
content: Bud 
aoVal: C
content: Bob 
Answer: B
Analysis: omitted 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Periodic Problems->Periodic Problems of Time->Period of Dates
Source: 其它
Problem: There are some ducks and chickens in a farm. The number of chickens is $10$ more than ducks.The number of ducks is half the number of chicken. How many ducks and chickens are there in the farm?  ~ 
Options:
aoVal: A
content: $26$ 
aoVal: B
content: $$30$$ 
aoVal: C
content: $$33$$ 
aoVal: D
content: $$39$$ 
aoVal: E
content: $$40$$ 
Answer: D
Analysis: $10+10+10=30$ 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules
Source: 其它
Problem: I ate half of an apple pie on Saturday and two thirds of the remainder on Sunday. What fraction of the pie was left for Monday? 
Options:
aoVal: A
content: None 
aoVal: B
content: $\frac12$ 
aoVal: C
content: $\frac13$ 
aoVal: D
content: $\frac23$ 
aoVal: E
content: $\frac16$ 
Answer: E
Analysis: $(1-\frac12)\times(1-\frac23)=\frac12\times\frac13=\frac16$. 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Solving Problems Involving Fractions and Percentages->Knowing the Base
Source: 其它
Problem: There were some cupcakes in a bakery. First, Jade ate half of the cupcakes. Then, Neil ate half of the remaining cupcakes. Finally, Terry ate $6$ and there were $$2$$ cupcakes left. At beginning, how many cupcakes were there in the bakery? 
Options:
aoVal: A
content: $$24$$ 
aoVal: B
content: $$32$$ 
aoVal: C
content: $$48$$ 
aoVal: D
content: $$12$$ 
Answer: B
Analysis: $$6+2=8$$  $$8+8=16$$  $$16+16=32$$ 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules
Source: 其它
Problem: If today is Tuesday, what day was it $$76$$ days ago? 
Options:
aoVal: A
content: $$$$Monday 
aoVal: B
content: $$$$Tuesday 
aoVal: C
content: $$$$Wednesday 
aoVal: D
content: $$$$Thursday 
Answer: C
Analysis: Today is Tues. $$77$$ days ago was Tues. $$76$$ days ago was Wed. 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Periodic Problems->Periodic Problems of Time
Problem: There is a piece of wire. First, half of the piece is used. Then, half of the remaining piece is used. Next, $$16$$ meters are used. Finally, $$9$$ meters are left. The original piece of the wire is~\uline{~~~~~~~~~~}~meters long. 
Options:
aoVal: A
content: $$36$$ 
aoVal: B
content: $$50$$ 
aoVal: C
content: $$64$$ 
aoVal: D
content: $$100$$ 
Answer: D
Analysis: $$16 + 9 = 25$$  $$25 + 25 =50$$  $$50 + 50 =100$$ 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules
Source: 其它
Problem: Karl is now $10$ years old, and Ala is $3$ years old. How many years from now will Karl be twice as old as Ala? 
Options:
aoVal: A
content: $$5$$ 
aoVal: B
content: $$10$$ 
aoVal: C
content: $$4$$ 
aoVal: D
content: $$1$$ 
aoVal: E
content: $$3$$ 
Answer: C
Analysis: The age difference is equal to $10-3=7$. When the age of Karl is twice the age of Ala, the age of Ala will be equal to the age difference which is $7$. Thus, it will pass $7-3 = 4$ years. 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Age Problems
Source: 其它
Problem: In a certain year, March $$27$$\textsuperscript{th}~is Friday. What day is April $$24$$\textsuperscript{th~}in this year?  $\textasciitilde$ 
Options:
aoVal: A
content: Monday 
aoVal: B
content: Tuesday 
aoVal: C
content: Thursday 
aoVal: D
content: Friday 
aoVal: E
content: Saturday 
Answer: D
Analysis: Counting from March $$27$$\textsuperscript{th}, after $31-27=4$ days it is March $$31$$\textsuperscript{st}. After $24$ days it is April $$24$$\textsuperscript{th}. In total, there are $4+24=28$ days. $28\div 7 =4$, which means April $$24$$\textsuperscript{th~}is Friday. 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Periodic Problems->Periodic Problems of Time
Problem: How many digits have to be written in order to write down every number from $$1$$ to $$100$$ inclusive? ($$2007$$ Math Kangaroo Problem, Level $$3-4$$, Question \#$$23$$) 
Options:
aoVal: A
content: $$100$$ 
aoVal: B
content: $$150$$ 
aoVal: C
content: $$190$$ 
aoVal: D
content: $$192$$ 
aoVal: E
content: $$200$$ 
Answer: D
Analysis: $1$-digit numbers: $9\times1=9$ digits.  $2$-digit numbers: $90\times2=180$ digits.  $3$-digit numbers: $1\times3=3$ digits.  Total: $9+180+3=192$. 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Page Number Problem->Correspondence between Numbers and Page Numbers->Applying the Total Number of Numbers
Problem: Ten years ago, the sum of the ages of my mother and father was $$71$$. What is the sum of their ages today? 
Options:
aoVal: A
content: $$51$$ 
aoVal: B
content: $$61$$ 
aoVal: C
content: $$81$$ 
aoVal: D
content: $$91$$ 
Answer: D
Analysis: Ten years ago, the sum of the ages of my mother and father was $$71$$. Each has aged $$10$$ years, so the sum of their ages is now $$91$$. 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Age Problems->Basic Relationships in Age Problems
Problem: The triplets Adam, Jan and Stas and their sister Marysia who is four years older than them were $24$ years old together three years ago. How old is Marysia today? (2001 Math Kangaroo Problem, Level 5-6, Question \#18) 
Options:
aoVal: A
content: $$5$$ 
aoVal: B
content: $$8$$ 
aoVal: C
content: $$9$$ 
aoVal: D
content: $$12$$ 
aoVal: E
content: $$15$$ 
Answer: D
Analysis: Adam, Jan and Stas were $(24-4)\div4=5$ years old three years ago. Marysia was $5+4=9$ years old. Thus, Marysia is $9+3=12$ years old. 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Age Problems
Source: 其它
Problem: A mother cut a cake into $$12$$ equal slices. Her four children had a slice each and she had one too. Later, a neighbour ate four slices. What percentage of the cake was left at the end of the day? 
Options:
aoVal: A
content: $$5\textbackslash\%$$ 
aoVal: B
content: $$10\textbackslash\%$$ 
aoVal: C
content: $$25\textbackslash\%$$ 
aoVal: D
content: $$35\textbackslash\%$$ 
aoVal: E
content: $$50\textbackslash\%$$ 
Answer: C
Analysis: $12-(4\times1)-1-4=3$  $\frac{3}{12}\times100\textbackslash\%=25\textbackslash\%$ 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Solving Problems Involving Fractions and Percentages->Finding the Rate
Problem: A worm is staying at the bottom of a well with a depth of $$13$$ metres. If it climbs up $$4$$ metres in the daytime and slips down $$1$$ metre at night, which day will it climb up to the ground? 
Options:
aoVal: A
content: The $$4$$th day 
aoVal: B
content: The $$5$$th day 
aoVal: C
content: The $$6$$th day 
aoVal: D
content: The $$7$$th day 
Answer: A
Analysis: It climbs up $$4$$ metres in the day time and slips down $$1$$ metre at night, so it climbs up $$3$$ metres in a whole day. For the first $$3$$ days, it climbs $$9$$ metres. During the day time of the forth day, it climbs $$4$$ metres and reaches the ground. Then it needs four days to climb up to the ground. 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Periodic Problems->Snail Climbing out of Well Problems
Problem: A bag of toffee is $7$ dollars, a bag of cotton candy is $6$ dollars, and a bag of orange candy is $15$ dollars. Now, the candy shop decides to mix $40$ bags of toffee, $50$ bags of cotton candy, and $10$ bags of orange candy for $100$ bags of assorted candy. What should be the price of the assorted candy in dollars to keep the total revenue unchanged? 
Options:
aoVal: A
content: $$7.3$$ 
aoVal: B
content: $$8$$ 
aoVal: C
content: $$9.5$$ 
aoVal: D
content: $$10$$ 
aoVal: E
content: $$12$$ 
Answer: A
Analysis: Total revenue: $40\times 7+50\times 6+10\times 15=730$ dollars  A bag of assorted candy: $$730\div 100=7.3$$ dollars 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Average Problems
Problem: A drawer contains $10$ yellow socks, $8$ blue socks and $4$ pink socks. Bella picks socks from the drawer without looking. What is the smallest number of socks she must pick to make sure she has at least one sock of each colour? 
Options:
aoVal: A
content: $$3$$ 
aoVal: B
content: $$4$$ 
aoVal: C
content: $$18$$ 
aoVal: D
content: $$19$$ 
Answer: D
Analysis: $10+8+1=19$ 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Average Problems ->Questions Involving Average->Extreme Value of Average
Source: 其它
Problem: Peter has some toy cars, and Paul has $$4$$ more toy cars than Peter. Altogether they have $$36$$ toy cars. How many toy cars does Paul have? 
Options:
aoVal: A
content: $$16$$ 
aoVal: B
content: $$48$$ 
aoVal: C
content: $$20$$ 
aoVal: D
content: $$12$$ 
Answer: C
Analysis: Paul has $$(36 + 4) \div 2 = 20$$ toy cars. 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Questions Involving Sum, Difference and Multiples->Problems Involving Sum and Difference->Sum and Differences Problems with multiple Variables
Source: 其它
Problem: There is an equation with all integers in the upper squares, and the answer on the right side is only the approximation of $$\frac{\square }{3}+\frac{\square }{5}+\frac{\square }{7}\approx 1.16$$ after rounding off. The numbers in each of the three upper squares of the equation are~\uline{~~~~~~~~~~}~in order. 
Options:
aoVal: A
content: $1,2,3$ 
aoVal: B
content: $1,3,5$ 
aoVal: C
content: $1,4,3$ 
aoVal: D
content: $2,1,2$ 
aoVal: E
content: $2,3,5$ 
Answer: A
Analysis: NA 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Equation Word Problems
Problem: Nancy has $23$ donuts. She gives one donut to Sana, and then Nancy has $10$ more donuts than Sana. At beginning, how many donuts does Sana have? 
Options:
aoVal: A
content: $$10$$ 
aoVal: B
content: $$11$$ 
aoVal: C
content: $$12$$ 
aoVal: D
content: $$13$$ 
aoVal: E
content: $$14$$ 
Answer: B
Analysis: $$23-1=22$$  $$22-10=12$$  $$12-1=11$$ 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules
Source: 其它
Problem: Joann\textquotesingle s birthday in $$2020$$ was May $$10$$\textsuperscript{th}, which was Sunday. Elizabeth\textquotesingle s birthday in $$2020$$ was June $$21$$\textsuperscript{st}. What day of the week is Elizabeth\textquotesingle s birthday on? 
Options:
aoVal: A
content: Thursday 
aoVal: B
content: Saturday 
aoVal: C
content: Sunday 
aoVal: D
content: Tuesday 
Answer: C
Analysis: It passed $$31-10 + 21 = 42$$ days in total. Since $$42 \div 7 = 6$$, it was Sunday. 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Periodic Problems->Periodic Problems of Time
Problem: A sugar solution is made by mixing $$7$$ ounces of sugar and $$21$$ ounces of water. Find the percent concentration of the solution. 
Options:
aoVal: A
content: $$20$$\% 
aoVal: B
content: $25$\% 
aoVal: C
content: $30$\% 
aoVal: D
content: $33.3$\% 
Answer: B
Analysis: $$7\div(7+21)=25\textbackslash\%$$. 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Concentration Problems->Basic Concentration Problems