2009 AMC 10B

Each morning of her five-day workweek, Jane bought either a $50$-cent muffin or a $75$-cent bagel. Her total cost for the week was a whole number of dollars. How many bagels did she buy?

Which of the following is equal to $$
\dfrac{\frac13-\frac14\ }{\ \frac12-\frac13\ }?
$$

Paula the painter had just enough paint for $30$ identically sized rooms. Unfortunately, on the way to work, three cans of paint fell off her truck, so she had only enough paint for $25$ rooms. How many cans of paint did she use for the $25$ rooms?

A rectangular yard contains two flower beds in the shape of congruent isosceles right triangles. The remainder of the yard has a trapezoidal shape, as shown. The parallel sides of the trapezoid have lengths $15$ and $25$ meters. What fraction of the yard is occupied by the flower beds?

Twenty percent less than $60$ is one-third more than what number?

Kiana has two older twin brothers. The product of their three ages is $128.$ What is the sum of their three ages?

By inserting parentheses, it is possible to give the expression $$
2\times3+4\times5
$$ several values. How many different values can be obtained?

In a certain year the price of gasoline rose by $20\%$ during January, fell by $20\%$ during February, rose by $25\%$ during March, and fell by $x\%$ during April. The price of gasoline at the end of April was the same as it had been at the beginning of January. To the nearest integer, what is $x?$

Segment $BD$ and $AE$ intersect at $C,$ as shown, $AB=BC=CD=CE,$ and $\angle A=\dfrac52\angle B.$ What is the degree measure of $\angle D?$

A flagpole is originally $5$ meters tall. A hurricane snaps the flagpole at a point $x$ meters above the ground so that the upper part, still attached to the stump, touches the ground $1$ meter away from the base. What is $x?$

How many $7$-digit palindromes (numbers that read the same backward as forward) can be formed using the digits $2,$ $2,$ $3,$ $3,$ $5,$ $5,$ $5?$

Distinct points $A,$ $B,$ $C,$ and $D$ lie on a line, with $AB=BC=CD=1.$ Points $E$ and $F$ lie on a second line, parallel to the first, with $EF=1.$ A triangle with positive area has three of the six points as its vertices. How many possible values are there for the area of the triangle?

As shown below, convex pentagon $ABCDE$ has sides $AB=3,$ $BC=4,$ $CD=6,$ $DE=3,$ and $EA=7.$ The pentagon is originally positioned in the plane with vertex $A$ at the origin and vertex $B$ on the positive $x$-axis. The pentagon is then rolled clockwise to the right along the $x$-axis. Which side will touch the point $x=2009$ on the $x$-axis?

On Monday, Millie puts a quart of seeds, $25\%$ of which are millet, into a bird feeder. On each successive day she adds another quart of the same mix of seeds without removing any seeds that are left. Each day the birds eat only $25\%$ of the millet in the feeder, but they eat all of the other seeds. On which day, just after Millie has placed the seeds, will the birds find that more than half the seeds in the feeder are millet?

When a bucket is two-thirds full of water, the bucket and water weigh $a$ kilograms. When the bucket is one-half full of water the total weight is $b$ kilograms. In terms of $a$ and $b,$ what is the total weight in kilograms when the bucket is full of water?

Points $A$ and $C$ lie on a circle centered at $O,$ each of $\overline{BA}$ and $\overline{BC}$ are tangent to the circle, and $\triangle ABC$ is equilateral. The circle intersects $\overline{BO}$ at $D.$ What is $\dfrac{BD}{BO}?$

Five unit squares are arranged in the coordinate plane as shown, with the lower left corner at the origin. The slanted line, extending from $(a,0)$ to $(3,3),$ divides the entire region into two regions of equal area. What is $a?$

Rectangle $ABCD$ has $AB=8$ and $BC=6.$ Point $M$ is the midpoint of diagonal $\overline{AC},$ and $E$ is on $\overline{AB}$ with $\overline{ME}\perp\overline{AC}.$ What is the area of $\triangle AME?$

A particular $12$-hour digital clock displays the hour and minute of a day. Unfortunately, whenever it is supposed to display a $1,$ it mistakenly displays a $9.$ For example, when it is $1{:}16$ PM the clock incorrectly shows $9{:}96$ PM. What fraction of the day will the clock show the correct time?

Triangle $ABC$ has a right angle at $B,$ $AB=1,$ and $BC=2.$ The bisector of $\angle BAC$ meets $\overline{BC}$ at $D.$ What is $BD?$