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2006 AMC 10B · #14Quadratics

Let aa and bb be the roots of the equation x2mx+2=0x^2-mx+2=0 . Suppose that a+1ba+\frac1b and b+1ab+\frac1a are the roots of the equation x2px+q=0x^2-px+q=0 . What is qq ?

2006 AMC 10B · #18Sequences & Series

Let a1,a2,...a_1 , a_2 , ... be a sequence for which a1=2a_1=2 , a2=3a_2=3 , and an=an1an2a_n=\frac{a_{n-1}}{a_{n-2}} for each positive integer n3n \ge 3 . What is a2006a_{2006} ?

2005 AMC 10A · #1Ratios, Percents & Averages

While eating out, Mike and Joe each tipped their server $2\$2 . Mike tipped 10%10\% of his bill and Joe tipped 20%20\% of his bill. What was the difference, in dollars, between their bills?

2005 AMC 10A · #2Functions

For each pair of real numbers aba \neq b , define the operation \star as (ab)=a+bab.(a \star b) = \frac{a+b}{a-b}. What is the value of ((12)3)((1 \star 2) \star 3) ?

2005 AMC 10A · #3Linear Equations & Word Problems

The equations 2x+7=32x + 7 = 3 and bx10=2bx - 10 = -2 have the same solution xx . What is the value of bb ?

2005 AMC 10A · #5Linear Equations & Word Problems

A store normally sells windows at $100\$100 each. This week the store is offering one free window for each purchase of four. Dave needs seven windows and Doug needs eight windows. How many dollars will they save if they purchase the windows together rather than separately?

2005 AMC 10A · #7Linear Equations & Word Problems

Josh and Mike live 1313 miles apart. Yesterday Josh started to ride his bicycle toward Mike's house. A little later Mike started to ride his bicycle toward Josh's house. When they met, Josh had ridden for twice the length of time as Mike and at four-fifths of Mike's rate. How many miles had Mike ridden when they met?

2005 AMC 10A · #10Quadratics

There are two values of aa for which the equation 4x2+ax+8x+9=04x^2 + ax + 8x + 9 = 0 has only one solution for xx . What is the sum of those values of aa ?

2005 AMC 10A · #13Exponents, Logarithms & Radicals

How many positive integers nn satisfy the following condition: (130n)50>n100>2200 ?\left(130n\right)^{50} > n^{100} > 2^{200} \ \text{?}

2005 AMC 10A · #17Sequences & Series

In the five-sided star shown, the letters AA , BB , CC , DD , and EE are replaced by the numbers 33 , 55 , 66 , 77 , and 99 , although not necessarily in this order. The sums of the numbers at the ends of the line segments AB\overline{AB} , BC\overline{BC} , CD\overline{CD} , DE\overline{DE} , and …

2005 AMC 10B · #1Ratios, Percents & Averages

A scout troop buys 10001000 candy bars at a price of five for 22 dollars. They sell all the candy bars at the price of two for 11 dollar. What was their profit, in dollars?

2005 AMC 10B · #2Ratios, Percents & Averages

A positive number xx has the property that x%x\% of xx is 44 . What is xx ?

2005 AMC 10B · #3Ratios, Percents & Averages

A gallon of paint is used to paint a room. One third of the paint is used on the first day. On the second day, one third of the remaining paint is used. What fraction of the original amount of paint is available to use on the third day?

2005 AMC 10B · #4Functions

For real numbers aa and bb , define ab=a2+b2a \diamond b = \sqrt{a^2 + b^2} . What is the value of (512)((12)(5))(5 \diamond 12) \diamond ((-12) \diamond (-5)) ?

2005 AMC 10B · #5Ratios, Percents & Averages

Brianna is using part of the money she earned on her weekend job to buy several equally-priced CDs. She used one fifth of her money to buy one third of the CDs. What fraction of her money will she have left after she buys all the CDs?

2005 AMC 10B · #6Ratios, Percents & Averages

At the beginning of the school year, Lisa's goal was to earn an AA on at least 80%80\% of her 5050 quizzes for the year. She earned an AA on 2222 of the first 3030 quizzes. If she is to achieve her goal, on at most how many of the remaining quizzes can she earn a grade lower than an AA ?

2005 AMC 10B · #11Sequences & Series

The first term of a sequence is 20052005 . Each succeeding term is the sum of the cubes of the digits of the previous term. What is the 2005th{2005}^{\text{th}} term of the sequence?

2005 AMC 10B · #16Quadratics

The quadratic equation x2+mx+nx^2+mx+n has roots twice those of x2+px+mx^2+px+m , and none of m,n,m,n, and pp is zero. What is the value of n/pn/p ?

2005 AMC 10B · #17Exponents, Logarithms & Radicals

Suppose that 4a=54^a = 5 , 5b=65^b = 6 , 6c=76^c = 7 , and 7d=87^d = 8 . What is abcda \cdot b\cdot c \cdot d ?

2004 AMC 10A · #1Linear Equations & Word Problems

You and five friends need to raise 15001500 dollars in donations for a charity, dividing the fundraising equally. How many dollars will each of you need to raise?

2004 AMC 10A · #2Functions

For any three real numbers aa , bb , and cc , with bcb\neq c , the operation \otimes is defined by: (a,b,c)=abc\otimes(a,b,c)=\frac{a}{b-c} What is ((1,2,3),(2,3,1),(3,1,2))\otimes(\otimes(1,2,3),\otimes(2,3,1),\otimes(3,1,2)) ?

2004 AMC 10A · #3Ratios, Percents & Averages

Alicia earns 20 dollars per hour, of which 1.45%1.45\% is deducted to pay local taxes. How many cents per hour of Alicia's wages are used to pay local taxes?

2004 AMC 10A · #4Absolute Value & Inequalities

What is the value of xx if x1=x2|x-1|=|x-2| ?

2004 AMC 10A · #6Linear Equations & Word Problems

Bertha has 6 daughters and no sons. Some of her daughters have 6 daughters, and the rest have none. Bertha has a total of 30 daughters and granddaughters, and no great-granddaughters. How many of Bertha's daughters and grand-daughters have no daughters?

2004 AMC 10A · #7Sequences & Series

A grocer stacks oranges in a pyramid-like stack whose rectangular base is 55 oranges by 88 oranges. Each orange above the first level rests in a pocket formed by four oranges below. The stack is completed by a single row of oranges. How many oranges are in the stack?