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2013 AMC 10B · #10Linear Equations & Word Problems

A basketball team's players were successful on 50% of their two-point shots and 40% of their three-point shots, which resulted in 54 points. They attempted 50% more two-point shots than three-point shots. How many three-point shots did they attempt?

2013 AMC 10B · #11Quadratics

Real numbers xx and yy satisfy the equation x2+y2=10x6y34x^2 + y^2 = 10x - 6y - 34 . What is x+yx+y ?

2013 AMC 10B · #13Sequences & Series

Jo and Blair take turns counting from 11 to one more than the last number said by the other person. Jo starts by saying " 11 ", so Blair follows by saying " 1,21, 2 " . Jo then says " 1,2,31, 2, 3 " , and so on. What is the 53rd number said?

2013 AMC 10B · #14Algebraic Manipulation

Define ab=a2bab2a\clubsuit b=a^2b-ab^2 . Which of the following describes the set of points (x,y)(x, y) for which xy=yxx\clubsuit y=y\clubsuit x ?

2013 AMC 10B · #19Quadratics

The real numbers c,b,ac,b,a form an arithmetic sequence with abc0a\ge b\ge c\ge 0 . The quadratic ax2+bx+cax^2+bx+c has exactly one root. What is this root?

2013 AMC 10B · #21Sequences & Series

Two non-decreasing sequences of nonnegative integers have different first terms. Each sequence has the property that each term, beginning with the third, is the sum of the previous two terms, and the seventh term of each sequence is NN . What is the smallest possible value of NN ?

2012 AMC 10A · #1Linear Equations & Word Problems

Cagney can frost a cupcake every 2020 seconds and Lacey can frost a cupcake every 3030 seconds. Working together, how many cupcakes can they frost in 55 minutes?

2012 AMC 10A · #3Absolute Value & Inequalities

A bug crawls along a number line, starting at 2-2 . It crawls to 6-6 , then turns around and crawls to 55 . How many units does the bug crawl altogether?

2012 AMC 10A · #5Linear Equations & Word Problems

Last year 100100 adult cats, half of whom were female, were brought into the Smallville Animal Shelter. Half of the adult female cats were accompanied by a litter of kittens. The average number of kittens per litter was 44 . What was the total number of cats and kittens received by the shelter last year?

2012 AMC 10A · #6Systems of Equations

The product of two positive numbers is 99 . The reciprocal of one of these numbers is 44 times the reciprocal of the other number. What is the sum of the two numbers?

2012 AMC 10A · #7Ratios, Percents & Averages

In a bag of marbles, 35\frac{3}{5} of the marbles are blue and the rest are red. If the number of red marbles is doubled and the number of blue marbles stays the same, what fraction of the marbles will be red?

2012 AMC 10A · #8Systems of Equations

The sums of three whole numbers taken in pairs are 1212 , 1717 , and 1919 . What is the middle number?

2012 AMC 10A · #10Sequences & Series

Mary divides a circle into 1212 sectors. The central angles of these sectors, measured in degrees, are all integers and they form an arithmetic sequence. What is the degree measure of the smallest possible sector angle?

2012 AMC 10A · #16Linear Equations & Word Problems

Three runners start running simultaneously from the same point on a 500500 -meter circular track. They each run clockwise around the course maintaining constant speeds of 4.44.4 , 4.84.8 , and 5.05.0 meters per second. The runners stop once they are all together again somewhere on the circular course. How many seconds do …

2012 AMC 10A · #17Algebraic Manipulation

Let aa and bb be relatively prime positive integers with a>b>0a>b>0 and a3b3(ab)3=733\dfrac{a^3-b^3}{(a-b)^3} = \dfrac{73}{3} . What is aba-b ?

2012 AMC 10A · #19Linear Equations & Word Problems

Paula the painter and her two helpers each paint at constant, but different, rates. They always start at 8:008:00 AM, and all three always take the same amount of time to eat lunch. On Monday the three of them painted 50% of a house, quitting at 4:004:00 PM. On Tuesday, when Paula wasn't there, the two helpers painted only …

2012 AMC 10A · #24Algebraic Manipulation

Let aa , bb , and cc be positive integers with aa\ge bb\ge cc such that \begin{align}a^2-b^2-c^2+ab&=2011\text{ and}\\ a^2+3b^2+3c^2-3ab-2ac-2bc&=-1997.\end{align} What is aa ?

2012 AMC 10B · #1Linear Equations & Word Problems

Each third-grade classroom at Pearl Creek Elementary has 18 students and 2 rabbits. How many more students than rabbits are there in all 4 of the third-grade classrooms?

2012 AMC 10B · #5Ratios, Percents & Averages

Anna enjoys dinner at a restaurant in Washington, D.C., where the sales tax on meals is 10%. She leaves a 15% tip on the price of her meal before the sales tax is added, and the tax is calculated on the pre-tip amount. She spends a total of 27.50 dollars for dinner. What is the cost of her dinner without tax or tip in …

2012 AMC 10B · #6Absolute Value & Inequalities

In order to estimate the value of xyx-y where xx and yy are real numbers with x>y>0x > y > 0 , Xiaoxi rounded xx up by a small amount, rounded yy down by the same amount, and then subtracted her rounded values. Which of the following statements is necessarily correct?

2012 AMC 10B · #7Linear Equations & Word Problems

For a science project, Sammy observed a chipmunk and a squirrel stashing acorns in holes. The chipmunk hid 3 acorns in each of the holes it dug. The squirrel hid 4 acorns in each of the holes it dug. They each hid the same number of acorns, although the squirrel needed 4 fewer holes. How many acorns did the chipmunk …

2012 AMC 10B · #8Absolute Value & Inequalities

What is the sum of all integer solutions to 1<(x2)2<251<(x-2)^2<25 ?

2012 AMC 10B · #13Linear Equations & Word Problems

It takes Clea 60 seconds to walk down an escalator when it is not operating, and only 24 seconds to walk down the escalator when it is operating. How many seconds does it take Clea to ride down the operating escalator when she just stands on it?

2011 AMC 10A · #1Linear Equations & Word Problems

A cell phone plan costs $20\$20 each month, plus 55 ¢ per text message sent, plus 1010 ¢ for each minute used over 3030 hours. In January Michelle sent 100100 text messages and talked for 30.530.5 hours. How much did she have to pay?

2011 AMC 10A · #3Functions

Suppose [a b][a\ b] denotes the average of aa and bb , and {a b c}\{a\ b\ c\} denotes the average of a,ba, b , and cc . What is {{1 1 0} [0 1] 0}\{\{1\ 1\ 0\}\ [0\ 1]\ 0\} ?