math-eval/TAL-SCQ5K huggingface dataset:
Problem: Bowen has $$40$$ grams of a $$25\textbackslash\%$$ sugar solution. After~\uline{~~~~~~~~~~}~of water evaporates, the percent concentration of the solution is $$40\textbackslash\%$$. (Evaporate: the water turns from liquid into vapor and is no longer in the solution anymore.) 
Options:
aoVal: A
content: $$15$$ grams 
aoVal: B
content: $$12$$ grams 
aoVal: C
content: $$9$$ grams 
aoVal: D
content: $$6$$ grams 
Answer: A
Analysis: $$40-40\times25\textbackslash\%\div40\textbackslash\%=40-25=15$$ grams. 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Concentration Problems->Finding and Making Use of Invariants
Problem: Tom goes to the supermarket to buy egg tarts. There are two kinds of egg tarts. One has $$6$$ tarts in the box and the other has $$10$$ tarts in the box. The unit price of the egg tarts is the same. If Tom wants $$76$$ egg tarts, how many boxes does he need at least?~(adapted from 2011 Math Kangaroo Problem, Level 3 - 4, Question \#10) 
Options:
aoVal: A
content: $$5$$ 
aoVal: B
content: $$8$$ 
aoVal: C
content: $$9$$ 
aoVal: D
content: $$11$$ 
aoVal: E
content: $$13$$ 
Answer: B
Analysis: $$76=10+10+10+10+10+10+10+6$$ 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Unitary Method Problems->Unitary Method with One Variable
Problem: A gift store buys some gifts at＄$$125$$ each. It wants to earn＄$$25 $$ for each gift after a discount of $$25 \textbackslash\% $$. What is the selling price before the discount for each gift? 
Options:
aoVal: A
content: $$160$$ dollars 
aoVal: B
content: $$180$$ dollars 
aoVal: C
content: $$190$$ dollars 
aoVal: D
content: $$200$$ dollars 
Answer: D
Analysis: $$\left( 125+25 \right)\div \left( 1-25 \textbackslash\% \right)=200$$ dollars. 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Word Problems in Economics->Basic Profit and Loss Concepts
Problem: It takes Mary $$30$$ minutes to walk uphill $$300 $$ m from her home to school, but it takes her only $$10$$ minutes to walk from school to home along the same route. What is her average speed, in m/min, for the round trip? (adapted from 2003 AMC 10 Problem, Question \#4) 
Options:
aoVal: A
content: $$10$$ 
aoVal: B
content: $$30$$ 
aoVal: C
content: $$20$$ 
aoVal: D
content: $$15$$ 
aoVal: E
content: $$12$$ 
Answer: D
Analysis: Mary walks a total of $$300+300=600\rm$$ meters in $$40$$ minutes.  Average speed: $600\div40=15$ m/min 
Knowledge points: Overseas Competition->Knowledge Point->Distance Word Problems->Distance Word Problems on Straight Road
Problem: If $$6$$ cans of Sweet Stuff Soda all together contain $$96$$ teaspoons of sugar, then there are a total of teaspoons of sugar in $$15$$ cans. 
Options:
aoVal: A
content: $$192$$ 
aoVal: B
content: $$208$$ 
aoVal: C
content: $$240$$ 
aoVal: D
content: $$270$$ 
aoVal: E
content: $$288$$ 
Answer: C
Analysis: If $$6$$ cans contain $$96$$ teaspoons of sugar, $$1$$ can contains $$96\div6 = 16$$ teaspoons of sugar. Thus $$15$$ cans contain $$16\times15 =240$$ teaspoons of sugar. 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Unitary Method Problems->Finding the Unit Rate and then the Total Value
Problem: Twenty-eight students from the fourth grade competed in a math competition. Each student earned a different number of points. The number of students who received more points than Tomek is two times smaller than the number of students who had fewer points than Tomek. In which position did Tomek finish that competition?~ ($2002$~Math Kangaroo Problem, Level $3-4$, Question \#$23$) 
Options:
aoVal: A
content: $$6$$\textsuperscript{th} 
aoVal: B
content: $10$\textsuperscript{th} 
aoVal: C
content: $8$\textsuperscript{th} 
aoVal: D
content: $9$\textsuperscript{th} 
aoVal: E
content: $7$\textsuperscript{th} 
Answer: B
Analysis: Except for Tomek, there are~$28-1=27$~students. The number of students who received more points than Tomek is~$27\div(2+1)=9$, so Tomek is in the~$9+1=10^{th}$~place. 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Questions Involving Sum, Difference and Multiples->Problems of Sum and Multiple
Source: 其它
Problem: January $$1$$, $$1989$$ was a Sunday. January $$1$$, $$1988$$ (a leap year) was a． 
Options:
aoVal: A
content: Friday 
aoVal: B
content: Saturday 
aoVal: C
content: Sunday 
aoVal: D
content: Monday 
Answer: A
Analysis: $$366$$ days $$=52$$ weeks $$2$$ days.  Jan $$1$$ $$1988$$ is $$52$$ weeks $$2$$ days before Jan $$1$$ $$1989$$. This date in $$1988$$ is $$2$$ days before Sunday so it is on a Friday. 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Periodic Problems->Periodic Problems of Time
Problem: Algebra books cost $$$12.50$$ each, and geometry books cost $$$14$$ each. How much do $$6$$ algebra books and $$5$$ geometry books cost in total? 
Options:
aoVal: A
content: $$$145.00$$ 
aoVal: B
content: $$$146.50$$ 
aoVal: C
content: $$$150.00$$ 
aoVal: D
content: $$$151.50$$ 
Answer: A
Analysis: Six algebra books cost $$$12.50 \times 6 = $75$$. Five geometry books cost $$$14\times5 = $70$$. All together, they cost a total of $$$145$$. 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Unitary Method Problems->Finding the Total Value using Unitary Method
Problem: A test is with a full score of $100$ points. Five students in a group wants to reach an average of $91$ points. If everyone scores a different whole number, the lowest score among them could be~\uline{~~~~~~~~~~}~. 
Options:
aoVal: A
content: $$60$$ 
aoVal: B
content: $$61$$ 
aoVal: C
content: $$67$$ 
aoVal: D
content: $$70$$ 
aoVal: E
content: $$71$$ 
Answer: B
Analysis: $91\times5-(100+99+98+97)=61$. 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Average Problems
Problem: Jack\textquotesingle s sister is $$22$$ years old, which is $$2$$ less than $$4$$ times Jack\textquotesingle s age. Assume Jack is $$x$$ years old, then． 
Options:
aoVal: A
content: $$x=4$$ 
aoVal: B
content: $$x=5$$ 
aoVal: C
content: $$x=6$$ 
aoVal: D
content: $$x=8$$ 
Answer: C
Analysis: The equation can represents this situation is $$4x-2=22$$,  so, $$4x=24$$, $$x=6$$.  So, the answer is $$6$$. 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Equation Word Problems
Problem: Jason and Ross are in line to check tickets. There are $36$ people in front of Jason and $16$ people behind. Ross happens to be in the middle of the entire line. How many people are there between Ross and Jason?~(adapted from 2000 Math Kangaroo Problem, Level 3 - 4, Question \#12) 
Options:
aoVal: A
content: $$18$$ 
aoVal: B
content: $$17$$ 
aoVal: C
content: $$16$$ 
aoVal: D
content: $$15$$ 
aoVal: E
content: $$14$$ 
Answer: D
Analysis: The total: $36+16+1=53$ , Jack\textquotesingle s location: $$(53-1)\div2=21$$, so there are $15$ people between Jack and Rose. 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Questions Involving Squares->Solid Squares->Basic Solid Square Problems
Problem: Amy mixes $$30$$ grams of a $$30\textbackslash\%$$ salt solution and $$20$$ grams of a $$20\textbackslash\%$$ salt solution together. How many grams of water should she add to the mixture to make it a $$10\textbackslash\% $$ solution? 
Options:
aoVal: A
content: $$70$$ 
aoVal: B
content: $$72$$ 
aoVal: C
content: $$75$$ 
aoVal: D
content: $$80$$ 
Answer: D
Analysis: $$30\times30\textbackslash\%+20\times 20\textbackslash\%=9+4=13$$ ounces.  $$13\div10\textbackslash\%-(30+20)=80$$ ounces. 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Concentration Problems->Finding and Making Use of Invariants
Problem: $$12$$ dogs are cqually divided into $$3$$ groups, how many dogs are there in each group. 
Options:
aoVal: A
content: $$3$$ 
aoVal: B
content: $$4$$ 
aoVal: C
content: $$6$$ 
aoVal: D
content: $$2$$ 
aoVal: E
content: $$12$$ 
Answer: B
Analysis: $$12\div3=4$$ 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules
Problem: My pet frog jumps $$3\text{m}$$ per jump. If it wants to jump from one end of a $$100\text{m}$$ field to another, the least number of jumps it will take is． 
Options:
aoVal: A
content: $$33$$ 
aoVal: B
content: $$34$$ 
aoVal: C
content: $$70$$ 
aoVal: D
content: $$97$$ 
Answer: B
Analysis: Since $$100\div 3=33$$ with remainder $$1$$, it takes my frog $$33$$ jumps to jump $$99\text{m}$$. It needs $$1$$ more jump, for $$34$$ jumps in all, to go at least $$100\text{m}$$. 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Unitary Method Problems->Unitary Method with One Variable
Problem: In $$2010$$, the Math Kangaroo competition is taking place in some schools for the $19$\textsuperscript{th}~time. Alice took part in the $10$\textsuperscript{th}~Math Kangaroo when she was $$9$$ years old. In what year was Alice born? (Adapted from 2008 Math kangaroo Problem, Level 3-4, Question \#9) 
Options:
aoVal: A
content: $$1996$$ 
aoVal: B
content: $$1994$$ 
aoVal: C
content: $$1992$$ 
aoVal: D
content: $$1990$$ 
aoVal: E
content: $$1988$$ 
Answer: C
Analysis: The $10$\textsuperscript{th}~Math Kangaroo was taking place in $2001$, which means that Alice was $9$ years old in $2001$, so she was born in $1992$. 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Periodic Problems->Periodic Problems of Time->Period of Time
Problem: Half a loaf of bread costs $$6$$ pence more than one-fourth of a loaf of bread. How many pence does a whole loaf of bread cost? 
Options:
aoVal: A
content: $$6$$ 
aoVal: B
content: $$12$$ 
aoVal: C
content: $$18$$ 
aoVal: D
content: $$24$$ 
aoVal: E
content: $$30$$ 
Answer: D
Analysis: One-fourth of a loaf of bread is ``$$1$$.'' Half a loaf of bread is ``$$2$$.''  One-fourth of a loaf of bread: $$6 \div (2-1) =6$$. A whole loaf of bread: $$6 \times 4 =24$$. 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Solving Problems Involving Fractions and Percentages->Finding the Base
Problem: Ben has $$9$$ pairs of shoes, of which $$4$$ shoes are red, $$2$$ shoes are bule, and the rest are green. How many pairs of shoes are green? 
Options:
aoVal: A
content: $$3$$ 
aoVal: B
content: $$6$$ 
aoVal: C
content: $$4$$ 
aoVal: D
content: $$5$$ 
aoVal: E
content: $$7$$ 
Answer: B
Analysis: $$9-2-1=6$$ 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Unitary Method Problems->Finding the Total Value using Unitary Method
Problem: Antonette gets $70 \textbackslash\%$ on a 10 -problem test, $80 \textbackslash\%$ on a 20 -problem test and $90 \textbackslash\%$ on a 30 -problem test. If the three tests are combined into one 60 problem test, which percent is closest to her overall score? (2006 AMC 8, Question \#12) 
Options:
aoVal: A
content: $$40$$ 
aoVal: B
content: $$77$$ 
aoVal: C
content: $$80$$ 
aoVal: D
content: $$83$$ 
aoVal: E
content: $$87$$ 
Answer: D
Analysis: $70 \textbackslash\% \cdot 10=7$ $80 \textbackslash\% \cdot 20=16$ $90 \textbackslash\% \cdot 30=27$ Adding them up gets $7+16+27=50$. The overall percentage correct would be $\frac{50}{60}=\frac{5}{6}=5 \cdot 16 . \overline{6}=83 . \overline{3} \approx(\mathbf{D}) 83$. 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Solving Problems Involving Fractions and Percentages->Percentages Word Problems
Source: 其它
Problem: Rick and Roy each stands at different ends of a straight road that is $$2021$$m long. They run toward each other. Rick\textquotesingle s speed is $$21\text{m/s}$$ and Roy\textquotesingle s speed is $$22\text{m/s}$$. They will meet in~\uline{~~~~~~~~~~}~seconds. 
Options:
aoVal: A
content: $$35$$ 
aoVal: B
content: $$4$$ 
aoVal: C
content: $$47$$ 
aoVal: D
content: $$50$$ 
Answer: C
Analysis: $$2021\div (21+22)=47$$. 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules
Problem: You have $12$ green cards and the ratio of your red cards to green cards is $3:2$. How many cards do you have? 
Options:
aoVal: A
content: $18$ 
aoVal: B
content: $20$ 
aoVal: C
content: $$24$$ 
aoVal: D
content: $30$ 
Answer: D
Analysis: $12$ is the product of $6$ and $2$.Then multiple $3$ by $6$ is the number of red cards. The total number of cards is $30$. 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Solving Problems Involving Proportions->Basic Units
Problem: Chloe and Zoe are both students in Ms. Demeanor\textquotesingle s math class. Last night they each solved half of the problems in their homework assignment alone and then solved the other half together. Chloe had correct answers to $80\textbackslash\%$ of the problems she solved alone, but overall $90\textbackslash\%$ of her answers were correct. Zoe had correct answers to $75\textbackslash\%$ of the problems she solved alone. What was Zoe\textquotesingle s overall percentage of correct answers? (2017 AMC 8, Question \#14) 
Options:
aoVal: A
content: $$87.5$$ 
aoVal: B
content: $$90$$ 
aoVal: C
content: $$92.5$$ 
aoVal: D
content: $$95.5$$ 
aoVal: E
content: $$100$$ 
Answer: A
Analysis: Assume the total amount of problems is 100 per half homework assignment, since we are dealing with percentages, and not values.  Then, we know that Chloe got 80 problems correct by herself, and got 180 problems correct overall.  We also know that Zoe had 75 problems she did correct alone.  We can see that the total amount of correct problems Chloe and Zoe did was $180-80=100$. Therefore Zoe has $100+75=175$ problems out of $200$ problems correct. Thus $\frac{175}{200} = 87.5$ percent. 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Solving Problems Involving Fractions and Percentages->Percentages Word Problems
Source: 其它
Problem: Mr. $$A$$ owns a home worth ＄$$10000$$. He sells it to Mr. $$B$$ at a $$10\textbackslash\%$$ profit based on the worth of the house. Mr. $$B$$ sells the house back to Mr. $$A$$ at a $$10\textbackslash\%$$ loss. Then: ($$1951$$ AHSME Problem, Question \#$$5$$) 
Options:
aoVal: A
content: $$A$$ comes out even 
aoVal: B
content: $$A$$ makes ＄$$1100$$ on the deal 
aoVal: C
content: $$A$$ makes ＄$$1000$$ on the deal 
aoVal: D
content: $$A$$ loses ＄$$900$$ on the deal 
aoVal: E
content: $$A$$ loses ＄$$1000$$ on the deal 
Answer: B
Analysis: Mr. $$ A$$ sells his home for $$(1 + 10\textbackslash\%)\times 10000$$ dollars$$= 1.1\times 10000$$ dollars$$ = 11000$$ dollars to Mr. $$ B$$. Then, Mr. $$ B$$ sells it at a price of $$(1- 10\textbackslash\%)\times 11000$$ dollars $$= 0.9\times 11000$$ dollars $$= 9900$$ dollars, thus $$11000- 9900=\boxed{ (\rm B) \textasciitilde A\textasciitilde makes\textasciitilde1100\textasciitilde on\textasciitilde the\textasciitilde deal}$$. 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Word Problems in Economics->Basic Profit and Loss Concepts
Problem: A $60\textbackslash\%$ alcohol solution contains $120$ grams of water. How many grams of solution are there? 
Options:
aoVal: A
content: $$200$$ 
aoVal: B
content: $$250$$ 
aoVal: C
content: $$300$$ 
aoVal: D
content: $$400$$ 
Answer: C
Analysis: $120\div(1-60\textbackslash\%)=300$ ounces. 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Concentration Problems
Problem: A, B, C, D and E sit around a circular table in that order. A starts by saying "$$100$$", B says "$$101$$", C says~"$$102$$" and so on round the table. Who will eventually say"$$2023$$"? 
Options:
aoVal: A
content: $$$$A 
aoVal: B
content: $$$$B 
aoVal: C
content: $$$$Cain 
aoVal: D
content: $$$$Devi 
aoVal: E
content: $$$$Emily 
Answer: D
Analysis: After Amit says "$$2015$$", there are $$5102-2015=3087$$ numbers remaining. Thus the counting goes round the table $$3087\div6= 514$$ times with a remainder of $$3$$, so the last to count is Devi. 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Periodic Problems->Periodic Problems of Circular Operations
Problem: Brown wants to put some board between his books. He has $10$ books in total. If he wants to put one board between every two adjacent books, how many boards does he need to prepare? 
Options:
aoVal: A
content: $$9$$ 
aoVal: B
content: $$10$$ 
aoVal: C
content: $$11$$ 
aoVal: D
content: $$12$$ 
aoVal: E
content: $$13$$ 
Answer: A
Analysis: $10 - 1 = 9$ 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Interval Problems
Source: 其它
Problem: In a class of $$18$$ students, $$6$$ are wearing jeans. What is the ratio of students wearing jeans to students not wearing jeans? 
Options:
aoVal: A
content: $$1:2$$ 
aoVal: B
content: $$1:3$$ 
aoVal: C
content: $$2:3$$ 
aoVal: D
content: $$2:1$$ 
Answer: A
Analysis: If $$6$$ students are wearing jeans, then $$18-6=12$$ are not. The ratio of students wearing jeans to students not wearing jeans is $$6:12=1:2$$. 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Solving Problems Involving Proportions->Dividing Quantities Based on Ratio
Problem: How many two-digit numbers are divisible by $3$ but not by $6$? 
Options:
aoVal: A
content: $$14$$ 
aoVal: B
content: $$15$$ 
aoVal: C
content: $$17$$ 
aoVal: D
content: $$30$$ 
aoVal: E
content: None of the above 
Answer: B
Analysis: There are $99$ $4-3 = 33$-multiples of $3$ less than $100$.  $3$ of them are one-digit numbers: $3$, $6$ and $9$.  Hence there are $30$ $2$-digit multiples of $3$.  Similarly, there are $96 + 6 -1 = 16 -1 = 15$ $2$-digit multiples of $6$.  Hence, the answer is 30 - 15 = \textbf{15.}  Answer： \textbf{(B)} 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Applying of Multiplication and Division
Source: 其它
Problem: Water from the first faucet fills the swimming pool in $70$ minutes. Water from each of the two other faucets fills the same swimming pool $3$ times faster. In how many minutes will the swimming pool be filled if all three faucets are opened? 
Options:
aoVal: A
content: $$210$$ 
aoVal: B
content: $$40$$ 
aoVal: C
content: $$30$$ 
aoVal: D
content: $$20$$ 
aoVal: E
content: $$10$$ 
Answer: E
Analysis: The efficiency of the first faucet is $\frac1{70}$ and that of the other two is $\frac3{70}$.  Thus, it takes $1\div (\frac1{70}+\frac3{70}\times2)=10$ minutes to fill the pool. 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Work Word Problems
Source: 其它
Problem: Chloe and Zoe are both students in Ms. Demeanor\textquotesingle s math class. Last night they each solved half of the problems in their homework assignment alone and then solved the other half together. Chloe had correct answers to $80\textbackslash\%$ of the problems she solved alone, but overall $90\textbackslash\%$ of her answers were correct. Zoe had correct answers to $75\textbackslash\%$ of the problems she solved alone. What was Zoe\textquotesingle s overall percentage of correct answers? (adapted from 2017 AMC 8, Question \#14) 
Options:
aoVal: A
content: $$87.5$$ 
aoVal: B
content: $$90$$ 
aoVal: C
content: $$92.5$$ 
aoVal: D
content: $$95.5$$ 
aoVal: E
content: $$100$$ 
Answer: A
Analysis: Assume the total amount of problems is 100 per half homework assignment, since we are dealing with percentages, and not values.  Then, we know that Chloe got 80 problems correct by herself, and got 180 problems correct overall.  We also know that Zoe had 75 problems she did correct alone.  We can see that the total amount of correct problems Chloe and Zoe did was $180-80=100$. Therefore Zoe has $100+75=175$ problems out of $200$ problems correct. Thus $\frac{175}{200} = 87.5$ percent. 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Solving Problems Involving Fractions and Percentages->Percentages Word Problems
Source: 其它
Problem: There is an empty tank which needs $29$ bottles of water to fill with. The workers pour $5$ bottles of water during the day, but uses $1$ bottle of water during the night. In how many days can the tank be filled with water? 
Options:
aoVal: A
content: $$5$$ 
aoVal: B
content: $$6$$ 
aoVal: C
content: $$7$$ 
aoVal: D
content: $$8$$ 
aoVal: E
content: $$9$$ 
Answer: C
Analysis: Every day: $5-1=4$ bottles.  $29\div4=7R1$  But for the last day, the tank can be filled with water without using during the night. 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules
Problem: The selling price of a sofa set is＄$$6500$$ and the profit percentage is $$30\textbackslash\%$$ for each set sold. If the cost of the sofa set is not changed, what is the profit percentage if the profit is ＄$$1200$$? 
Options:
aoVal: A
content: $$20\textbackslash\%$$ 
aoVal: B
content: $$24\textbackslash\%$$ 
aoVal: C
content: $$25\textbackslash\%$$ 
aoVal: D
content: $$30\textbackslash\%$$ 
Answer: B
Analysis: $$6500\div(1+30\textbackslash\%)=5000$$, $$1200\div5000=24\textbackslash\%$$. 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Word Problems in Economics->Basic Profit and Loss Concepts
Problem: Owen sees an archery right after he entered the carnival. After Owen takes 20 shots, he has made $55 \textbackslash\%$ of his shots. After he takes 5 more shots, he raises his percentage to $56 \textbackslash\%$. How many of the last 5 shots did she make?~ (adapted from 2004 AMC 8, Question\#6) 
Options:
aoVal: A
content: $$1$$ 
aoVal: B
content: $$2$$ 
aoVal: C
content: $$3$$ 
aoVal: D
content: $$4$$ 
aoVal: E
content: $$5$$ 
Answer: C
Analysis: Owen made $0.55 * 20=11$ shots originally. Letting $x$ be the number of shots she made, we have $\frac{11+x}{25}=0.56$. Solving for $x$ gives us $x=$ (C) 3 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Solving Problems Involving Fractions and Percentages->Percentages Word Problems
Source: 其它
Problem: I read $1$ page of a book on Nov $1$, $2$ pages on Nov $2$, $3$ pages on Nov $3$, and so on. I followed this pattern for the whole month. Altogether, how many pages did I read in November? 
Options:
aoVal: A
content: $$30$$ 
aoVal: B
content: $$31$$ 
aoVal: C
content: $$465$$ 
aoVal: D
content: $$496$$ 
Answer: C
Analysis: There are in total $30$ days in Nov.  $1+2+3+4+\cdots+30=(1+30)\times30\div2=465$ 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Page Number Problem
Problem: Chloe and Zoe are both students in Ms. Demeanor\textquotesingle s math class. Last night they each solved half of the problems in their homework assignment alone and then solved the other half together. Chloe had correct answers to $90 \textbackslash\%$ of the problems she solved alone, but overall $84 \textbackslash\%$ of her answers were correct. Zoe had correct answers to $80 \textbackslash\%$ of the problems she solved alone. What was Zoe\textquotesingle s overall percentage of correct answers? (adapted from 2017 AMC 8, Question \#14) 
Options:
aoVal: A
content: $$79$$ 
aoVal: B
content: $$82$$ 
aoVal: C
content: $$84$$ 
aoVal: D
content: $$86$$ 
aoVal: E
content: $$88$$ 
Answer: A
Analysis: Assume the total amount of problems is $100$ per half homework assignment, since we are dealing with percentages, and not values. Then, we know that Chloe got $90$ problems correct by herself, and got $168$ problems correct overall. We also know that Zoe had $80$ problems she did correct alone. We can see that the total amount of correct problems Chloe and Zoe did was $168-90=78$. Therefore Zoe has $80+78=158$ problems out of $200$ problems correct. This is (C) $79$ percent. 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Solving Problems Involving Fractions and Percentages->Percentages Word Problems
Source: 其它
Problem: If $$15^{}\text{th}$$April is Friday, what day of the week is $$1$$\textsuperscript{st~}April ? 
Options:
aoVal: A
content: Sunday　 
aoVal: B
content: Monday　 
aoVal: C
content: Wednesday　 
aoVal: D
content: Friday　 
aoVal: E
content: Saturday　 
Answer: D
Analysis: There are 14 days between $$1$$\textsuperscript{st~}April and $$15^{}\text{th}$$April.  14 days = 2 week  Therefore, $$1$$\textsuperscript{st~}April is Friday. 
Knowledge points: Overseas Competition->Knowledge Point->Word Problem Modules->Periodic Problems->Periodic Problems of Time