Practice (EndingDigits,TheDivideByNineMethod,MODBasic)

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The game of Connex contains one 4-unit piece, two identical 3-unit pieces, three identical 2-unit pieces and four identical 1-unit pieces. How many different arrangements of pieces will make a 10-unit segment? The 10-unit segments consisting of the pieces 4-3-2-1 and 1-2-3-4 are two such arrangements to include.


In square units, what is the largest possible area a rectangle inscribed in the triangle shown here can have?


A line segment with endpoints A(3, 1) and B(2, 4) is rotated about a point in the plane so that its endpoints are moved to A' (4, 2) and B' (7, 3), respectively. What are the coordinates of the center of rotation? Express your answer as an ordered pair.

Let $\triangle ABC$ be a right triangle whose three sides' lengths are all integers. Prove among its three sides' lengths, at lease one is a multiple of $3$, one is a multiple of $4$, and one is a multiple of $5$. (Note: they can be the same side. For example, in the $5-12-13$, $12$ is both a multiple of $3$ and $4$.)


Before the last game of the basketball season, Jonas had scored 88 points. He scored 23 points in the last game, making his season average 18.5 points per game. How many games did Jonas play during the season?

The dart board shown here contains 20 uniquely numbered sectors. When Malaika aims for a particular number, she hits it half the time. The other half of the time, she randomly hits an adjacent number on either side with equal probability. The number in the sector that her dart hits is the number of points scored. Trying to earn the highest possible score, Malaika decides to aim for the same number for each of her next 20 throws. Based on the given information, for which number should Malaika aim?


Joy is riding her bicycle up a hill. After traveling 3 km, Joy passes Greg, who is walking down the hill at a rate of 1 m/s. Joy continues up the hill for another 7 km before riding down at double the average speed she rode up. Joy and Greg arrive at Joy\u2019s starting point at the same moment. In meters per second, what was Joy's average speed going down the hill?

In rectangle ABCD, BC = 2AB. Points O and M are the midpoints of $\overline{AD}$ and $\overline{BC}$ , respectively. Point P bisects $\overline{AO}$ . If OB = $6\sqrt{2}$ units, what is the area of $\triangle{NOP}$?


If $40q = p + \frac{p}{3}+\frac{p}{9}+\frac{p}{27}$ , what is the ratio $\frac{q}{p}$? Express your answer as a common fraction.

What is the length of the shortest segment that can be drawn from the point (4, 1) to 2x - y + 4 = 0? Express your answer as a decimal to the nearest hundredth.

How many positive two-digit integers have exactly $8$ positive factors?

In right $\triangle{ABC}$, shown here, AC = 24 units and BC = 7 units. Point D lies on $\overline{AB}$ so that $\overline{CD} \perp \overline{AB}$. The bisector of the smallest angle of $\triangle{ABC}$ intersects $\overline{CD}$ at point E. What is the length of $\overline{ED}$ ? Express your answer as a common fraction.


The single-digit prime numbers 2, 3, 5 and 7 are used to replace $a$, $b$, $c$ and $d$ in the multiplication table shown here. The four products are found and then added together. What is the greatest possible value of this sum?


The circular pizza, shown here, is cut 5 times with straight line cuts before being removed from the pan. What is the maximum number of pieces that can be made which contain none of the pizza's outer crust, located around its circumference?


After tossing a red, then a green and, finally, a white standard six-faced die, Patrick used the numbers showing on the upper faces of each die, in order, to create the incorrect equation below, such that red - green = white. By rotating each die a quarter turn in some direction so that the number on the top face moves to a lateral face, he finds that he can make a correct equation. Given that the opposite faces of a die have a sum of 7, how many correct equations are possible?


A square prism has dimensions $5' \times 5' \times 10'$, where ABCD is a square. AP = ER = 2 ft and QC = SG = 1 ft. The plane containing $\overline{PQ}$ and $\overline{RS}$ slices the original prism into two new prisms. What is the volume of the larger of these two prisms?


What is the sum of all real numbers $x$ such that $4^x - 6 \times 2^x + 8 = 0$?

In square units, what is the area of the region bounded by the graph of |x \u2013 y| + |x + y| = 6 ?

How many collections of six positive, odd integers have a sum of $18$? Note that $1 + 1 + 1 + 3 + 3 + 9$ and $9 + 1 + 3 + 1 + 3 + 1$ are considered to be the same collection.


In how many different ways can $15,015$ be represented as the sum of two or more consecutive positive integers written in ascending order?

Call a positive integer squarish if it contains the digits of the squares of its digits in order but not necessarily contiguous. For example, $14263$ contains $1^2 = 1$, $4^2 = 16$ and $2^2 = 4$. However, it is not squarish because it does not contain $3^2 = 9$, and $6^2 = 36$ is not in order. What is the smallest squarish number that includes at least one digit greater than $1$?

A square of side length 1 inch is drawn with its center A on a circle O of radius 1 inch such that a side of the square is perpendicular to $\overline{OA}$ , as shown. What is the area of the shaded region? Express your answer as a decimal to the nearest hundredth.


Marti lives in New York and wishes to call her friend Kathy who lives in Honolulu. The chart below shows the times in several cities when it is 12:00 noon in New York. If Marti calls Kathy when the time is 6:30 p.m. in New York, what time is it in Honolulu?


Place 9 points in a unit square. Prove it is possible to select 3 points from them to create a triangle whose area is no more than $\frac{1}{8}$.

What is the value of $1 - 2 + 4 -8 + 16 - 32 + 64 - 128 + 256 -512 + 1024$?