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All Questions
+0
230622 Questions
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240
1
Probability
A positive integer divisor of 11 is chosen at random. What is the probability that this divisor is prime? Express your answer as a common fraction.
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Guest
Jul 12, 2022
0
207
1
+166
Counting
Consider the sequence such that and for every positive integer , , where is the largest prime factor of . The first few terms of the sequence are . What is the largest value of such that is a four-digit number?
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RainbowSquirrel53
Jul 12, 2022
0
131
0
help plz
Bertrand has 12 cards: on the front of each card is a digit, and on the back of each card is either a triangle, square, pentagon or circle. Bertrand looks through the pile of cards and says to his friend Georg, "For each card in the pile, if the number
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Guest
Jul 12, 2022
0
200
1
Algebra
If 3a + b + c = -3, a+3b+c = 9, a+b+3c = 1, then find abc.
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Guest
Jul 12, 2022
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218
3
Help
Let and be the solutions of the equation . What is the value of ?
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Guest
Jul 12, 2022
0
213
1
Digits
If n = 10^{2020} + 10^{2019} + 10^{2018} + 10^{2017} + ... + 10^2 + 10^1, what is the sum of digits of the integer n?
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Guest
Jul 12, 2022
-2
215
1
geometry
In the figure, triangle ABC is inscribed in a semicircle with diameter AC of length 20 inches, and AB = 10 inches. When the area of the shaded region, in square inches, is expressed in the form a*pi - b what is the value of a + b?
read more ..
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Guest
Jul 12, 2022
0
122
0
triples
Find the number of triples (a, b, c) of positive integers, such that 1 <= a, b, c <= 100 and
a^2 + b^2 + c^2 = ab + ac + bc + 4.
Guest
Jul 12, 2022
-2
128
0
how
did you do that
Guest
Jul 12, 2022
0
169
2
Polynomials
Let p(x) be a monic polynomial of degree 6 such that p(1) = 1, p(2) = 2, p(3) = 3, p(4) = 4, p(5) = 25, and p(6) = 6. Find p(7).
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Guest
Jul 12, 2022
0
121
0
system
If w, x, y, and z are real numbers satisfying:
w + x + y = -2
w + x + z = 4
w + y + z = 9
read more ..
Guest
Jul 12, 2022
0
200
1
Algebra
If x and y are positive integers for which 3x + 2y + xy = 117, then what is x + y?
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Guest
Jul 12, 2022
0
220
2
Algebra
Find 1/(a - 1) + 1/(b - 1) where a and b are the roots of the quadratic equation 2x^2-7x+2 = x^2-11x+1.
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Guest
Jul 12, 2022
0
121
0
Arithmetic sequence
Let a1, a2, a3, ... be an arithmetic sequence. If a2/a4 = 3, what is a5/a3?
Guest
Jul 12, 2022
0
206
1
Complex sum
What is the value of the sum where z ranges over all 7 solutions (real and nonreal) of the equation z^7 = -1?
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Guest
Jul 12, 2022
0
124
0
geometry
In triangle ABC, points D and F are on AB and E is on AC such that DE || BC and EF || CD. If AF = 9 and DF = 2, then what is BD?
Guest
Jul 12, 2022
0
143
0
trig problem
Calculate
As usual, the output of an inverse trig function should be in radians.
Guest
Jul 12, 2022
0
187
2
Help on this card game related problem please
In the card game Set, each card features a number of shapes, with four attributes:
Number: The number of shapes is 1, 2, or 3.
Color: Each shape is red, purple, or green.
Shape: Each shape is oval, diamond, or squiggle.
Shading: Each shape
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Guest
Jul 12, 2022
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165
0
Probability
In a regular icosagon (20-sided polygon), all the diagonals are drawn. If a diagonal is selected at random, what is the probability of selecting a diagonal that is either the shortest possible length, the second-shortest possible length, or the third-shortest
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Guest
Jul 12, 2022
0
203
1
Number Theory
x,y, and z are positive integers such that gcd(x, y, z) = 14 and lcm(x, y, z) = 630 and y = 3x. What is the smallest possible value of x + y + z?
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Guest
Jul 12, 2022
+11
278
3
+1162
One of my friend's questions from high school. LOL
If
then for how many values of x is ?
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nerdiest
Jul 12, 2022
0
135
0
Counting
A haiku is a poem with three lines: the first line contains 5 syllables, the second line 7 syllables, and the last line 5 syllables. If each word in each list shown is used at most once, how many different haiku can be made with these
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Guest
Jul 12, 2022
0
176
1
Percent
If 2/3 of 75% of 0.8x is equal to 100, what is 4/3 of 60% of 0.75x? Express your answer as a decimal to the nearest tenth.
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Guest
Jul 12, 2022
0
205
1
Prisms
Both of the right triangular prisms shown have bases that are right triangles with hypotenuse length 10 cm. One prism has height x and a base leg of length 6 cm. The other prism has height x - 2 cm and a base leg of length 5*sqrt(2) cm.
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Guest
Jul 12, 2022
0
226
2
Rates
While driving, Carl notices that his odometer reads 25,952 miles, which happens to be a palindrome. He thought this was pretty rare, but 2.5 hours later, his odometer reads as 36,563 miles, anoher palindrome. What was Carl's average speed during
read more ..
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Guest
Jul 12, 2022
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