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All Questions
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233683 Questions
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13
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+2115
Algebra
Compute
\frac{1}{1 \times 4} + \frac{1}{4 \times 7} + \frac{1}{7 \times 10}
LiIIiam0216
May 18, 2024
0
10
1
+2115
Algebra
Compute
1 + \frac{3}{6} + \frac{5}{9} + \frac{7}{12} + \dotsb.
●
LiIIiam0216
May 18, 2024
0
12
0
+2115
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?
read more ..
LiIIiam0216
May 18, 2024
0
3
1
+311
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);
read more ..
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Lilliam0216
May 18, 2024
0
4
1
+311
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?
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Lilliam0216
May 18, 2024
0
7
1
+2115
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
0
9
0
+2115
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
0
12
0
+2115
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
May 17, 2024
0
10
0
+2115
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
0
6
0
+2115
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
0
2
2
+13
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 )
read more ..
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Dysoncloud
May 17, 2024
+1
11
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
0
7
0
+2115
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
0
7
1
+2115
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
0
8
0
+2115
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
0
9
0
+2115
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
read more ..
LiIIiam0216
May 17, 2024
0
4
1
+311
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
0
12
0
+729
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.
read more ..
eramsby1O1O
May 17, 2024
0
4
2
+729
Algebra
Solve the inequality 2x - 5 <= -x + 12 - 7x + 18.
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eramsby1O1O
May 17, 2024
0
6
1
+2115
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
0
6
1
+2115
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
0
9
0
+2115
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
read more ..
LiIIiam0216
May 17, 2024
0
8
1
+2115
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
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