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All Questions
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231304 Questions
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1
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+1186
Geometry
In triangle $PQR,$ let $X$ be the intersection of the angle bisector of $\angle P$ with side $\overline{QR}$, and let $Y$ be the foot of the perpendicular from $X$ to side $\overline{PR}$. If $PQ = 8,$ $QR = 5,$ and $PR = 1,$ then compute the length
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LiIIiam0216
50
mins ago
0
1
0
+1186
Algebra
In a store window, there was a box of berries having a total weight of 200 kg. The berries were 98% water, by weight. After two days in the sun, the water content of the berries was only 95%, by weight. What was the total weight of the berries
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LiIIiam0216
52
mins ago
0
1
0
+1186
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 $S_1 = \frac{1}{5}$ and $S_2 = \frac{1}{10},$ then find $S_{15}.$
LiIIiam0216
1 hour ago
0
1
0
+1186
Algebra
In class, we derived that
\frac{1}{n(n + 1)} = \frac{1}{n} - \frac{1}{n + 1}.
Fill in the blanks to make a true equation:
\frac{5x}{(x - 1)(x^2 + 2)(x + 7)^3)} = \frac{A}{x - 1} + \frac{Bx + C}{x^2 + 2} + \frac{D}{x + 7}
read more ..
LiIIiam0216
2 hours ago
0
1
0
+1186
Algebra
Compute
\frac{1}{1 \times 4} + \frac{1}{4 \times 7} + \frac{1}{7 \times 10}
LiIIiam0216
2 hours ago
0
1
0
+1186
Algebra
Compute
1 + \frac{3}{6} + \frac{5}{9} + \frac{7}{12} + \dotsb.
LiIIiam0216
2 hours ago
0
1
0
+1186
Help Algebra
Let S be the set of all real numbers of the form
a1/3 + a2/3^2 + a3/3^3 + ....
where a_i \in {0, 1, 2} for all i.
(a) Is the number 1/7 in the set S?
(b) Is the number 1/4 in the set S?
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LiIIiam0216
3 hours ago
0
1
0
+182
Expected value
The grid below is made up of line segments, like the line segment in red.
[asy] unitsize(1 cm); int i; for (i = 0; i <= 3; ++i) { draw((i,0)--(i,2)); } for (i = 0; i <= 2; ++i) { draw((0,i)--(3,i)); } draw((3,1)--(3,2), linewidth(2*bp) + red);
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Lilliam0216
3 hours ago
0
1
0
+182
6 and 5
A stick is broken at two points, chosen at random. If the length of the stick is 6 units, then what is the probability that all three resulting pieces are shorter than 5 units?
Lilliam0216
3 hours ago
0
1
1
+1186
Algebra
All members of our painting team paint at the same rate. If $40$ members can paint a $100$ square foot wall in $50$ minutes, then how long would it take the $40$ members to paint a $480$ square foot wall, in minutes?
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LiIIiam0216
May 18, 2024, 12:03 AM
0
1
0
+1186
Algebra
All members of our painting team paint at the same rate. If $45$ members can paint a specific wall in $60$ minutes, then how long would it take $12$ members to paint the same wall, in minutes?
LiIIiam0216
May 18, 2024, 12:03 AM
0
1
0
+1186
Algebra
I drove to the beach at a rate of $40$ miles per hour. If I had driven at a rate of $55$ miles per hour instead, then I would have arrived $25$ minutes earlier. How many miles did I drive?
LiIIiam0216
May 18, 2024, 12:03 AM
May 17, 2024
0
1
0
+1186
Algebra
Compute the unique positive integer $n$ such that
2 \cdot 2^2 + 3 \cdot 2^3 + 4 \cdot 2^4 + \dots + n \cdot 2^n = 32.
LiIIiam0216
May 17, 2024, 10:12 PM
0
1
0
+1186
Algebra
Find the value of $k$ so that
3 + \frac{3 + k}{4^2} + \frac{3 + 2k}{4^4} + \frac{3 + 4k}{4^6} + \dotsb = 8.
LiIIiam0216
May 17, 2024, 10:12 PM
0
1
2
+8
help pls
Problem:
Report Error
Lizzie came up with a divisibility test for a certain number :
Break a positive integer into two-digit chunks, starting from the ones place. (For example, the number would break into the two-digit chunks )
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Dysoncloud
May 17, 2024, 10:06 PM
+1
1
0
+34
Quadratics
A rocket is launched with a velocity of 1200 ft/sec from the ground. How long until it hits the ground?
Hint: Use
jilin73
May 17, 2024, 10:03 PM
0
1
0
+1186
Algebra
Let $r$ be the positive real solution to $x^3 + \frac{2}{5} x - 1 = x^3 - 3x + 7.$ Find the exact numerical value of
r^2 + 2r^5 + 3r^8 + 4r^{11} + \dotsb.
LiIIiam0216
May 17, 2024, 9:35:56 PM
0
1
1
+1186
Algebra
Our badminton team has finished $75\%$ of its season. So far, we have won $35\%$ of the games we played. What percent of the remainder of our games must we win in order to finish the season with the same number of wins as losses?
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LiIIiam0216
May 17, 2024, 7:46:08 PM
0
1
0
+1186
Algebra
The system of equations
\[\frac{xy}{x + y} = 1, \quad \frac{xz}{x + z} = 1, \quad \frac{yz}{y + z} = 5\]
has exactly one solution. What is $z$ in this solution?
LiIIiam0216
May 17, 2024, 7:45:46 PM
0
1
0
+1186
Algebra
Alice and Bob each have a certain amount of money. If Alice receives $n$ dollars from Bob, then she will have $10$ times as much money as Bob. If, on the other hand, she gives $n$ dollars to Bob, then she will have $4$ times as much money as
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LiIIiam0216
May 17, 2024, 7:45:06 PM
0
1
0
+182
Stick and probability
A stick is broken at two points, chosen at random. If the length of the stick is 6 units, then what is the probability that all three resulting pieces are shorter than 5 units?
Lilliam0216
May 17, 2024, 7:39:34 PM
0
1
0
+234
Algebra
I own a large truck, and my neighbor owns four small trucks that are all identical. My truck can carry a load of at least $500$ pounds more than each of her trucks, but no more than $\frac{1}{4}$ of the total load her four trucks combined can carry.
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eramsby1O1O
May 17, 2024, 6:36:16 PM
0
1
1
+234
Algebra
Solve the inequality 2x - 5 <= -x + 12 - 7x + 18.
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eramsby1O1O
May 17, 2024, 6:23:32 PM
0
1
1
+1186
Coordinates
Fill in the blanks with integers, and select the correct operator ($+$ or $-$), to give an equation whose graph is the line that passes through the point $(-1,8)$ and is parallel to the graph of $4x + 3y = -8 - x - 15y.$
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LiIIiam0216
May 17, 2024, 5:42:11 PM
0
1
1
+1186
Coordinates
Line $\ell_1$ represents the graph of $3x + 2y = -14 - 8x + 5y$. Line $\ell_2$ passes through the point $(5,-6)$, and is perpendicular to line $\ell_1$. Write the equation of line $\ell_2$ in the form $y=mx +b$.
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LiIIiam0216
May 17, 2024, 5:41:52 PM
0
1
0
+1186
Algebra
Here is a summary of some inequality rules.
Fill in the blanks to complete the rules. (The first rule is already complete.)
You can add or subtract the same quantity from both sides.
You can multiply/divide both sides by
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LiIIiam0216
May 17, 2024, 5:41:34 PM
0
1
1
+1186
Algebra
All members of our painting team paint at the same rate. If $50$ members can paint a $3600$ square foot wall in $20$ minutes, then how long would it take for $25$ members to paint a $4000$ square foot wall, in minutes?
●
LiIIiam0216
May 17, 2024, 4:59:53 PM
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