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Post New Question
All Questions
+0
237750 Questions
0
47
1
+490
Counting
I have $4$ different mathematics textbooks and $3$ different psychology textbooks. In how many ways can I place the $7$ textbooks on a bookshelf, in a row, if all the psychology textbooks are together?
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MeIdHunter
Dec 14, 2024
0
41
1
+490
Counting
A speech class has $4$ freshmen and $3$ sophomores. (Everyone is distinguishable.) In how many ways can they stand in line, so that all of the freshmen are standing next to each other?
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MeIdHunter
Dec 14, 2024
Dec 13, 2024
0
56
1
+810
Geometry
In trapezoid EFGH, \overline{EF} \parallel \overline{GH}, and P is the point on \overline{EH} such that EP:PH = 1:2. If the area of triangle PEF is 6, and the area of triangle PGH is 6, then find the area of trapezoid EFGH.
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crimefightingvigiI
Dec 13, 2024
0
58
1
+810
Geometry
Altitudes AD and BE of acute triangle ABC intersect at point H. If angle ABH = 30 and angle DAC = 45, then what is angle HCA in degrees?
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crimefightingvigiI
Dec 13, 2024
0
56
1
+810
Geometry
We have a triangle $\triangle ABC$ and a point $K$ on $BC$ such that $AK$ is an altitude to $\triangle ABC$. If $AC = 8,$ $BK = 2$, and $CK = 3,$ then what is $AB$?
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crimefightingvigiI
Dec 13, 2024
0
55
0
+810
Geometry
Two tangents $\overline{PA}$ and $\overline{PB}$ are drawn to a circle, where $P$ lies outside the circle, and $A$ and $B$ lie on the circle. The length of $\overline{AB}$ is $4,$ and the circle has a radius of $5.$ Find the length $AB.$
crimefightingvigiI
Dec 13, 2024
0
1
47
1
+417
Geometry
Two tangents $\overline{PA}$ and $\overline{PB}$ are drawn to a circle, where $P$ lies outside the circle, and $A$ and $B$ lie on the circle. The length of $\overline{AB}$ is $4,$ and the circle has a radius of $5.$ Find the length $AB.$
read more ..
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nathanl6656
Dec 13, 2024
0
54
0
+417
Geometry
Lines $XQ$ and $XR$ are tangent to a circle, as shown below. If $\angle XTU = 47^\circ$ and $\angle QAU = 65^\circ,$ then find $\angle QXR,$ in degrees.
nathanl6656
Dec 13, 2024
0
1
38
1
+417
Geometry
A circular table is pushed into a corner of the room, where two walls meet at a right angle. A point P on the edge of the table (as shown below) has a distance of 6 from one wall, and a distance of 6 from the other wall. Find the radius of the
read more ..
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nathanl6656
Dec 13, 2024
0
46
1
+417
Geometry
Points $A,$ $B,$ and $C$ are given in the coordinate plane. There exists a point $Q$ and a constant $k$ such that for any point $P$,
PA^2 + PB^2 + PC^2 = 3PQ^2 + k.
If $A = (7,-11),$ $B = (10,13),$ and $C = (18,-22)$, then find the constant
read more ..
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nathanl6656
Dec 13, 2024
0
33
1
+85
Direct Variation
The weight of a bag of golf balls varies directly as the number of golf balls in the bag. If a bag of 69 golf balls weighs 2,553 grams, how many golf balls are in a bag that weighs 1,110 grams?
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Alyssiaca
Dec 13, 2024
Dec 12, 2024
0
69
0
+608
Number Theory
What are the first 5 digits after the decimal point (technically the hexadecimal point...) when the fraction \frac{2}{23} is written in base 16?
onyuIee
Dec 12, 2024
0
54
0
+613
Number Theory
When $N$ is divided by $10$, the remainder is $a$. When $N$ is divided by $2$, the remainder is $b$. What is $N$ modulo $20$, in terms of $a$ and $b$?
Pythagorearn
Dec 12, 2024
0
39
1
+613
Number Theory
An eccentric baseball card collector wants to distribute her collection among her descendants. If she divided her cards among her $13$ great-great-grandchildren, there would be $8$ cards left over. If she divided her cards among her $10$ great-grandchildren,
read more ..
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Pythagorearn
Dec 12, 2024
0
48
0
+613
Number Theory
Carlos wants to send Cecil a message encrypted with RSA. Cecil has published his public encryption exponent $3$ and his public modulus $3$. When Carlos encrypts the number $3$ with this system, what is the result?
Pythagorearn
Dec 12, 2024
0
53
0
+613
Number Theory
The House of Lilliput is using RSA encryption to receive secret messages from all the realms. They have published their public encoding exponent $e = 8$ and their public modulus $M = pq = 6$.
Break the code: Find their secret decoding
read more ..
Pythagorearn
Dec 12, 2024
0
45
1
+417
Geometry
Let $O$ be the origin. Points $P$ and $Q$ lie in the first quadrant. The slope of line segment $\overline{OP}$ is $4,$ and the slope of line segment $\overline{OQ}$ is $5.$ If $OP = OQ,$ then compute the slope of line segment $\overline{PQ}.$
Note:
read more ..
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nathanl6656
Dec 12, 2024
0
64
0
+417
Geometry
Let $a$ and $b$ be real numbers, where $a < b$, and let $A = (a,a^2)$ and $B = (b,b^2)$. The line $\overline{AB}$ (meaning the unique line that contains the point $A$ and the point $B$) has slope $2$. Find $a + b$.
nathanl6656
Dec 12, 2024
0
55
0
+417
Geometry
In triangle $ABC,$ the angle bisector of $\angle BAC$ meets $\overline{BC}$ at $D.$ If $\angle BAC = 60^\circ,$ $\angle CAD = 45^\circ,$ and $AD = 24,$ then find the area of triangle $ABC.$
nathanl6656
Dec 12, 2024
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