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All Questions
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238019 Questions
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A number is chosen at random from among all 9-digit numbers that use each of the digits 1 through 9 exactly once. What is the probability that this number is a multiple of 2?
gnistory
Apr 21, 2026
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1
0
+226
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Let ABC be a triangle with \angle B = 90^{\circ}. Suppose that point D lies on segment BC such that angle BAD = \angle CAD, and suppose that point E lies on segment AC such that angle EDA = 60^{\circ}. Given that AD = AC and that CE = 17, find BD.
<
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HumanBemg
Apr 21, 2026
0
1
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+226
help
In the diagram below, AB = AC = 1, and arc BC is centered at A with \angle BAC = 60^\circ. Point D is on \overline{AB}, and point E is on arc BC so that BD = DE, and arc BE (centered at D) is tangent to \overline{AC}. Point F is on \overline{DB},
read more ..
HumanBemg
Apr 21, 2026
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1
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+105
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Two chords with length r are drawn on a circle of radius r. What is the maximum possible distance between their endpoints?
Jyrgernry
Apr 21, 2026
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1
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+105
help
William writes the integers from 2 through 15 from left to right on a piece of paper, then does the following:
* He begins by circling the leftmost uncircled integer, then circles all its powers. Afterwards, he repeats this process until every
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Jyrgernry
Apr 21, 2026
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1
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+890
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Siva starts at vertex A of square ABCD with side length 10. He walks towards vertex C, along the diagonal AC. He then walks towards B, then towards D. What is the length of his path?
cooIcooIcooI17
Apr 21, 2026
0
1
0
+890
help
Mrs. Monstrous Millie wants to throw a party for a group of monsters and aliens. The monsters each have 5 heads with 7 ears on each head, and the aliens each have 5 heads with 3 ears on each head. As party favors, Mrs. Millie wants to give each guest a
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cooIcooIcooI17
Apr 21, 2026
0
2
0
+105
helpme
Given regular heptagon ABCDEFG, a circle can be drawn that is tangent to DC at C and to EF at F. What is radius of the circle if the side length of the heptagon is 1?
Jyrgernry
Apr 21, 2026
0
2
0
+105
help
In the diagram, a semicircle is centered at $O,$ and $\overline{AB}$ is tangent to the semicircle at $B.$ Find $\angle BCD,$ in degrees.
Jyrgernry
Apr 21, 2026
Apr 20, 2026
0
1
1
+890
help
The triangle with vertices at (1,0), (0,1), and (k,k) has area 1/2. Find k.
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cooIcooIcooI17
Apr 20, 2026
0
1
2
+890
help
Distinct prime numbers p, q, and r satisfy the equation p(q + r) = 16. Which of the following prime numbers must either q or r be equal to?
2 3 5 7 11
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cooIcooIcooI17
Apr 20, 2026
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1
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+665
help
In triangle ABC, let D be a point on side BC. Select all the true statements.
If AD is an altitude of triangle ABC, then AC > AD.
If AD is a median of triangle ABC, then BD > CD.
If AD is an angle bisector
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Pythagorearn
Apr 20, 2026
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1
0
+665
help
All the sides of a triangle have integer length. The perimeter of the triangle is 10, and the triangle is scalene. How many such non-congruent triangles are there?
Pythagorearn
Apr 20, 2026
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1
0
+275
help
In triangle $XYZ,$ circles are drawn centered at $X$, $Y$, and $Z$, so that all pairs of circles are externally tangent. If $XY = 2,$ $XZ = 2,$ and $YZ = 2$, then find the sum of the areas of all three circles.
CInsbstnkng
Apr 20, 2026
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1
0
+275
help
In the diagram below, chords $\overline{AB}$ and $\overline{CD}$ are perpendicular, and meet at $X.$ Find the diameter of the circle.
CInsbstnkng
Apr 20, 2026
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1
0
+226
help
In equiangular octagaon EFGHIJKL, we know that EF = GH = IJ = KL = 1 and FG = HI = JK = LE = sqrt(2). Find the area of the octagon.
HumanBemg
Apr 20, 2026
-1
1
0
+226
help
Semicircles are drawn on diameters \overline{AB} and \overline{CD}, as shown below. Find AB.
HumanBemg
Apr 20, 2026
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1
0
+665
Help
Given regular heptagon ABCDEFG, a circle can be drawn that is tangent to DC at C and to EF at F. What is radius of the circle if the side length of the heptagon is 1?
Pythagorearn
Apr 20, 2026
0
1
0
+665
help
In the diagram, a semicircle is centered at $O,$ and $\overline{AB}$ is tangent to the semicircle at $B.$ Find $\angle BCD,$ in degrees.
Pythagorearn
Apr 20, 2026
0
1
0
+228
Help
The graph of y = p(x)/q(x) is shown below, where p(x) and q(x) are quadratic. (Assume that the grid lines are at integers.)
The horizontal asymptote is x = 0 and the only vertical asymptote is y = 0. Find p(3)/q(3)
BlackoutMiIkshake
Apr 20, 2026
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1
0
+228
Help
Triangle ABC is rotated clockwise about A to triangle $AB'C',$ as shown in the diagram. We know the length of the path taken by vertex $B$ is $6.$ What is the length of the path taken by vertex $C?$
BlackoutMiIkshake
Apr 20, 2026
0
1
0
+228
Help
Two circles C_1 and C_2 are shown below. Find the radius of the circle that is externally tangent to both $C_1$ and $C_2,$ and tangent to the $x$-axis.
BlackoutMiIkshake
Apr 20, 2026
0
1
0
+1844
help
Triangle PQR is rotated clockwise about P to triangle PQ'R', as shown in the diagram. We know the length of the path taken by vertex Q is the same as the length of the path takesn by P. What is the length of the path taken by vertex R?
blackpanther
Apr 20, 2026
0
1
0
+1844
help
Line \ell is shown below. The line y = 2x + k has a distance of 3 from line y = 5x + k. Find all possible values of k.
blackpanther
Apr 20, 2026
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