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Post New Question
All Questions
+0
236050 Questions
0
7
0
+948
Geometry
In right triangle $ABC,$ $\angle C = 90^\circ$. Median $\overline{AM}$ has a length of 1, and median $\overline{BN}$ has a length of 1. What is the length of the hypotenuse of the triangle?
Rangcr897
Oct 29, 2024
0
5
0
+346
Algebra
Let a and b be the solutions to 7x^2 + x - 5 = -3x^2 - 9x - 4. Compute (a - 4)/(b - 4) + (b - 4)/(a - 4).
nathanl6656
Oct 29, 2024
0
3
1
+346
Algebra
Seven years ago, Grogg's dad was $9$ times as old as Grogg. Four years ago, Grogg's dad was $6$ times as old as Grogg. How old is Grogg's dad currently?
●
nathanl6656
Oct 29, 2024
0
6
2
+346
Algebra
Pearl writes down seven consecutive integers, and adds them up. The sum of the integers is equal to 28/9 times the largest of the seven integers. What is the smallest integer that Pearl wrote down?
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nathanl6656
Oct 29, 2024
0
7
0
+346
Algebra
Find the number of ordered pairs $(a,b)$ of integers such that
\frac{a + 2}{a + 1} = \frac{b}{8}.
nathanl6656
Oct 29, 2024
0
7
0
+267
Number Theory
Find the 4000th digit following the decimal point in the expansion of \frac{1}{17}.
bIueb3rry
Oct 29, 2024
0
5
0
+267
Number Theory
How many bases b \ge 2 are there such that 100_b + 1_b is prime?
bIueb3rry
Oct 29, 2024
0
4
0
+267
Number Theory
Let $p$ be a prime. What are the possible remainders when $p$ is divided by $17?$ Select all that apply.
bIueb3rry
Oct 29, 2024
0
4
0
+551
Number Theory
Find the number of ordered triples (a,b,c) of positive integers that satisfy
a = \gcd(b,c) + 33
b = \gcd(a,c) + 25
c = \gcd(a,b) + 35
Pythagorearn
Oct 29, 2024
0
4
0
+551
Number Theory
Let a, b, c, d be distinct positive integers such that {lcm}(a, b, c, d) < 1000 and a + b + c + d = 1000. Find the largest possible value of a + b.
Pythagorearn
Oct 29, 2024
0
9
0
+667
Number Theory
Find the largest positive integer n for which there exist positive integers a, b, and c such that
\gcd(a + 3b, b + 3c, c + 3a) = nabc
siIviajendeukie
Oct 29, 2024
0
6
0
+667
Number Theory
Let N be the number of ordered 6-tuples (a_1, a_2, a_3, a_4, a_5, a_6) of positive integers that satisfy
\frac{1}{a_1} + \frac{1}{a_2} + \frac{1}{a_3} + \frac{1}{a_4} + \frac{1}{a_5} + \frac{1}{a_6} = 6.
Find the remainder when N is divided
read more ..
siIviajendeukie
Oct 29, 2024
0
9
0
+667
Number Theory
Let a, b, and c be integers such that 7a + 4b = 3c. Find the largest integer that always divides $abc$.
siIviajendeukie
Oct 29, 2024
0
5
1
+842
Counting
Xavier and Yvonne meet one day at a cafe. For any day that Xavier goes to the cafe, the probability that Xavier goes the next day is $\frac{1}{2},$ and the probability that Xavier returns in two days is $\frac{1}{2}.$ For any day that Yvonne
read more ..
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RedDragonl
Oct 29, 2024
0
4
1
+842
Counting
Find the number of subsets S of \{0, 1, 2, 3, \dots, 15\} that have the following property: If n is in S, and m \equiv n + 1 \pmod{16}$ with $0 \le m \le 15,$ then m is also in S.
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RedDragonl
Oct 29, 2024
0
7
0
+510
Counting
Let A and B be two fixed points in the plane such that the distance between them is $1.$ Point $P$ is chosen at random on the circle centered at $A$ with radius $1,$ and point $Q$ is chosen at random on the circle centered at $B$ with radius $1.$
read more ..
onyuIee
Oct 29, 2024
0
4
0
+510
Counting
In the $4 \times 4$ grid of points below, each point is one unit away from its closest neighbor. In how many ways are there to choose four of these points, such that the distance between any two chosen points is at most \sqrt{2}?
onyuIee
Oct 29, 2024
0
9
0
+510
Counting
Five workers $A,$ $B,$ $C,$ $D,$ and $E$ at a coffee stand are working out a schedule for the next $10$ days. The schedule must satisfy the following conditions:
* There must be exactly two workers every day, and every pair of workers must be
read more ..
onyuIee
Oct 29, 2024
0
5
0
+182
Geometry
The sides of convex quadrilateral ABCD are AB = 8, BC = 5, $CD = 5,$ and $DA = 8.$ Diagonals $\overline{AC}$ and $\overline{BD}$ intersect at $E$ so that $BE:ED = 1:1.$ Find the area of ABCD.
AUnVerifedTaxPayer
Oct 29, 2024
0
6
0
+182
Geometry
Let H be the orthocenter of acute triangle ABC, and let M be the midpoint of \overline{AC}. Ray $\overrightarrow{MH}$ intersects the circumcircle of triangle $ABC$ at $P.$ If $BC < AB,$ $\angle ABP = 60^\circ,$ $MH = 14,$ and $HP = 3,$ then
read more ..
AUnVerifedTaxPayer
Oct 29, 2024
0
4
0
+478
Geometry
Triangle ABC has a right angle at B. Point D lies on side \overline{AC} such that CD = 6. The circle with diameter $\overline{CD}$ intersects $\overline{AB}$ at two distinct points, $E$ and $F,$ with $AE < AF.$ If AE = 6 and DE = 4,
read more ..
ChiIIBill
Oct 29, 2024
0
6
0
+478
Geometry
In right triangle ABC, \angle ACB = 90^\circ, and the legs are a = BC and b = AC. Let $S$ and $T$ be points on $\overline{AC}$ and $\overline{BC},$ respectively. Let $R$ be the foot of the altitude from $S$ to $\overline{AB},$ and let $U$ be
read more ..
ChiIIBill
Oct 29, 2024
0
8
0
+478
Geometry
In tetrahedron ABCD, AB = AC = AD = 12 and BC = BD = CD = 12. There is a sphere that is tangent to all six edges of the tetrahedron. Find the radius of this sphere.
ChiIIBill
Oct 29, 2024
0
8
0
+606
Algebra
Let the roots of z^{99} = 1 be z_k = x_k + iy_k for 1 \le k \le 99, where $x_k$ and $y_k$ are real. Let $P(z)$ be the monic polynomial whose roots are x_k - iy_k,$ for $1 \le k \le 99.$ Compute P(-2).
cooIcooIcooI17
Oct 29, 2024
0
5
1
+781
Algebra
Find the number of positive integers n \le 10000 that satisfy
\lfloor \log_4 n \rfloor + \lfloor \log_8 n \rfloor + \lfloor \log_{64} n \rfloor = 5
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booboo44
Oct 29, 2024
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