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Post New Question
All Questions
+0
237313 Questions
0
49
0
+900
Number Theory
Let N be a positive integer. The number N has three digits when expressed in base 7. When the number N is expressed in base 18, it has the same three digits, in reverse order. What is N? (Express your answer in decimal
read more ..
eramsby1O1O
Jul 1, 2024
Jun 30, 2024
+1
31
1
+21
Combinatorics
Erica and Alan each flip a fair coin 5 times. Suppose that Erica has flipped more heads than Alan after each has flipped the coin 2 times. The probability that Erica has flipped more heads than Alan after each has flipped the coin 5 times is m n , where
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Sxchen1110
Jun 30, 2024
0
39
0
+972
Number Theory
For a certain positive integer $n$, the number $n^{6873}$ leaves a remainder of $3$ when divided by $23.$ What remainder does $n$ leave when divided by $23$?
Rangcr897
Jun 30, 2024
0
30
0
+972
Number Theory
For an integer $n,$ let $f(n)$ be the remainder when $n^8 + n^{16}$ is divided by $5.$ Compute $f(0) + f(1) + f(2) + f(3) + f(4).$
Rangcr897
Jun 30, 2024
0
34
1
+972
Algebra
Fill in the coefficients:
n(n - 1)(n + 17)(n - 21)(n - 33) = n^5 + ___ n^4 + ___ n^3 + ___ n^2 + ___n + ___
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Rangcr897
Jun 30, 2024
0
29
0
+972
Algebra
The Fibonacci sequence is defined by F_1 = F_2 = 1 and F_{n + 2} = F_{n + 1} + F_n. Find the remainder when F_{1000} is divided by 17.
Rangcr897
Jun 30, 2024
+2
26
1
+280
Geometry
In triangle $PQR$, let $M$ be the midpoint of $\overline{PQ}$, let $N$ be the midpoint of $\overline{PR}$, and let $O$ be the intersection of $\overline{QN}$ and $\overline{RM}$, as shown. If $\overline{QN}\perp\overline{PR}$, $QN = 15$, and $PR = 20$,
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ABJelly
Jun 30, 2024
0
18
1
+1782
Geometry
In triangle ABC, angle ACB = 90 degrees. Let H be the foot of the altitude from C to side AB.
If BC = 1 and AH = 2, find CH.
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blackpanther
Jun 30, 2024
0
27
1
+972
Algebra
The sequence $a_1$, $a_2$, $a_3,$ $\dots$ is defined by $a_1 = 1,$ $a_2 = 3,$ and
a_n = 2a_{n - 1} + a_{n - 2}.
Thus, the next few terms are $a_3 = 2a_2 + a_2 = 6 + 1 = 7$ and $a_4 = 2a_3 + a_2 = 14 + 3 = 17$.
Find
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Rangcr897
Jun 30, 2024
0
26
0
+1782
Geometry
In trapezoid $PQRS,$ $\overline{PQ} \parallel \overline{RS}$. Let $X$ be the intersection of diagonals $\overline{PR}$ and $\overline{QS}$. The area of triangle $PQX$ is $2,$ and the area of triangle $RSX$ is $2.$ Find the area of trapezoid
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blackpanther
Jun 30, 2024
+3
19
2
+19
Algebra
How many three-digit palindromes (numbers that read the same forward and backward) satisfy the following property: the sum of three things -- the hundreds digit, the units digit, and the product of the units and tens digits -- is eight more than the tens
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DeluluSunshine
Jun 30, 2024
0
35
0
+972
Number Theory
The number $N$ is a multiple of $7$. The base $2$ representation of $N$ is
10011010011ABC110_2.
Compute the ordered triple of digits $(A,B,C)$.
Rangcr897
Jun 30, 2024
+1
30
1
+972
Number Theory
Find a six-digit multiple of $64$ that consists only of the digits $2$ and $4$.
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Rangcr897
Jun 30, 2024
0
32
0
+972
Counting
Find the number of $7$-digit numbers, where the sum of the digits is divisible by $11.$
Rangcr897
Jun 30, 2024
0
37
0
+972
Counting
In how many ways can the numbers 1, 2, 3, 4, 5, 6 be arranged in a row, so that the product of any two adjacent numbers is at least 5?
Rangcr897
Jun 30, 2024
0
25
1
+950
Algebra
Solve the system of equations
y = \log_2 (2x)
y = log_4 (16 + x)
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gnistory
Jun 30, 2024
0
18
1
+950
Algebra
Find all points $(x,y)$ that are $5$ units away from the point $(2,7)$ and that lie on the line $y = 5x - 28.$
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gnistory
Jun 30, 2024
0
31
0
+950
Algebra
Let $f(x) = 3x - 8 + 4x^2$ and $g(x) = 15x + c - 3x^2$. Find $c$ if $(f \circ g)(x) = (g \circ f)(x)$ for all $x$.
gnistory
Jun 30, 2024
0
30
1
+950
Algebra
Let $a_1,$ $a_2,$ $a_3,$ $\dots$ be an arithmetic sequence. Let $S_n$ denote the sum of the first $n$ terms. If $S_{20} = \frac{1}{5}$ and $S_{10} = 0,$ then find $S_{70}.$
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gnistory
Jun 30, 2024
0
38
1
+950
Algebra
Laverne starts counting out loud by 5's. She starts with 2. As Laverne counts, Shirley sums the numbers Laverne says. When the sum finally exceeds 20, Shirley runs screaming from the room. What number does Laverne say that sends
read more ..
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gnistory
Jun 30, 2024
+1
31
1
+5
solve this pls its kinda hard
Let be the roots of . Let . Then the product can be expressed as a polynomial in . Find this polynomial.
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asdasdasddwasdwasd
Jun 30, 2024
0
40
0
+950
Algebra
Let a_1, a_2, a_3, \dots, a_{10}, a_{11}, a_{12} be an arithmetic sequence. If $a_1 + a_3 + a_5 + a_7 + a_9 + a_{11} = 0$ and $a_2 + a_4 + a_6 + a_8 + a_{10} + a_{12} = 0$, then find $a_1$.
gnistory
Jun 30, 2024
0
37
0
+950
Algebra
When the same constant is added to the numbers 60, 120, and 160, a three-term geometric sequence arises. What is the common ratio of the resulting sequence?
gnistory
Jun 30, 2024
0
35
0
+950
help hard algebra
Let $x$ and $y$ be real numbers such that $x^3 + 3xy^2 = 679$ and $x^3 - 3xy^2 = 615.$ Find $x - y.$
gnistory
Jun 30, 2024
0
25
1
+950
Algebra
Fill in the blanks to get an identity. (Each blank should contain an integer.)
(n - k + 2)^2 = __ n^2 + ___ k^2 + ___ n + ___k + ___ nk + ___
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gnistory
Jun 30, 2024
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