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All Questions
+0
235731 Questions
0
36
1
+1533
Counting digits
Sam writes down the numbers $1,$ $2,$ $\dots,$ $315,$ $316,$ $317,$ $\dots,$ $249,$ $250.$
(a) How many digits did Sam write, in total?
(b) Sam chooses one of the digits written down at random. What is the probability that Sam chooses
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parmen
Mar 10, 2024
-1
15
1
+743
Polygon
Let P1 P2 P3 ... P10 be a regular polygon inscribed in a circle with radius 1. Compute
(P1 P2)^2 + (P2 P3)^2 + ... + (P1 P10)^2.
The sum includes all terms of the form (Pi Pi + 1)^2, where 1 <= i <= 9. We
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hairyberry
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bingboy
Mar 10, 2024
0
9
1
+743
Semicircle
In triangle $ABC,$ $\angle C = 90^\circ.$ A semicircle is constructed along side $\overline{AC}$ that is tangent to $\overline{BC}$ and $\overline{AB}.$ If the radius of the semicircle is equal to $1$ and $BC = \sqrt{3}$, then find $AB$.
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bingboy
Mar 10, 2024
-1
29
1
+1443
help solve
Pearl writes down seven consecutive integers, and adds them up. The sum of the integers is equal to $7$ times the largest of the seven integers. What is the smallest integer that Pearl wrote down?
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blackpanther
Mar 10, 2024
-1
24
1
+1443
Algebra
If I give my brother $5$ dollars, then we will have the same amount of money. If instead he gives me $10$ dollars, then I'll have twice as much money as he will have. How much money does my brother currently have (in dollars)?
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blackpanther
Mar 10, 2024
-1
12
1
+1443
Algebra
Five times a number is divided by $2$ more than that number. If the result is $6,$ then what was the original number?
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blackpanther
Mar 10, 2024
-1
41
0
+1443
help algebra
Find all values of $a$ that satisfy the equation
\[\frac{a}{3} + 1 = \frac{a + 3}{a} - \frac{a^2 + 2}{a}.\]
blackpanther
Mar 10, 2024
Mar 9, 2024
0
26
1
+479
Rotation
Let A1, A2, A3., ..., A15, A16 be a regular polygon. A rotation centered at A4 with an angle of X takes A3 to A5. Given that X < 180, find X in degrees.
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ChiIIBill
Mar 9, 2024
0
14
1
+479
dilation
A dilation with scale factor k takes figure A to figure B. Find the sum of all possible values of k.
Figure
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ChiIIBill
Mar 9, 2024
0
29
1
+479
Dilation
Point B is the image of point A under a dilation with center O. If OB = 60, and the scale factor of the dilation is 4, then what is OA?
O---A-----B
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ChiIIBill
Mar 9, 2024
0
23
1
+479
Parabola
The parabola $y = ax^2 + bx + c$ is graphed below. Find $a \cdot b \cdot c.$ (The grid lines are one unit apart.)
The graph passes through (-3,5), (-1,7), and (2,-1).
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ChiIIBill
Mar 9, 2024
0
24
1
+704
Coordinates
Find the coordinates of the center of the circle.
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booboo44
Mar 9, 2024
0
17
1
+704
Geometry
In trapezoid $EFGH,$ $\overline{EF} \parallel \overline{GH},$ and $P$ is the point on $\overline{EH}$ such that $EP:PH = 1:2$. If the area of triangle $EF = 3$ and $HG = 10$, and the height of the trapezoid is $6$, then find the area of triangle
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booboo44
Mar 9, 2024
0
29
1
+704
Quadrilaterals
Quadrilateral $ABCD$ is a parallelogram. Let $E$ be a point on $\overline{AB},$ and let $F$ be the intersection of lines $DE$ and $BC.$ The area of triangle $EAD$ is $9.$ If $AE:EB = 3:4$ and the height of parallelogram $ABCD$ is $10$,
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booboo44
Mar 9, 2024
0
18
1
+704
Trapezoid
In trapezoid $ABCD,$ $\overline{AB} \parallel \overline{CD}$. Find the area of the trapezoid.
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booboo44
Mar 9, 2024
0
29
1
+850
Line Equation
Find the equation whose graph is shown below. Write your answer in standard form.
(Standard form is $Ax+By = C$, where $A$ is positive, and $A$, $B$, and $C$ are integers with greatest common divisor $1$.)
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magenta
Mar 9, 2024
0
20
0
+850
Geometry
In rectangle $EFGH$, let $M$ be the midpoint of $\overline{EF}$, and let $X$ be a point such that $MH = MX$, as shown below. If $\angle EFH = 30^\circ$ and $\angle MHX = 60^\circ,$ then find $\angle XHG,$ in degrees.
magenta
Mar 9, 2024
0
29
0
+850
Geometry
In the diagram, chords $\overline{XY}$ and $\overline{VW}$ are extended to meet at $U.$ If $\angle U = 30^\circ$, minor arc $XY$ is $180^\circ$, and minor arc $VW$ is $90^\circ$. Find arc $WY$, in degrees.
magenta
Mar 9, 2024
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