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A two digit number |
2011-03-01 |
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jhoanna pose la question :
the sum of the digits of a two digit number is 10. The value of the number is 16 times the units digit.Find the number.
Penny Nom lui répond. |
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Ordering fractions |
2011-03-01 |
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amanda pose la question :
I am utterly confused my son needs to order 3 different fractions from least to greatest such as 3/6, 5/6 & 4/6 I read your explanation on how to do it but I was still confused is there a more simpler method?
Robert Dawson lui répond. |
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Find the dimension of the original rectangle |
2011-02-28 |
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sandra pose la question :
the perimeter of a rectangle is 40 cm. if the length were doubled and the width halved, the perimeter would be increased by 16cm. Find the dimension of the original rectangle
Robert Dawson lui répond. |
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A region bounded by a chord and an arc |
2011-02-28 |
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Gene pose la question :
find the area of a segment bounded by a chord and a 45 degree arc of a 36" circle
Robert Dawson lui répond. |
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Converting base 3 to 5 |
2011-02-28 |
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Harry pose la question :
Hey Math Central, I came across your website and im in need of help on my maths c assignment. I have to convert base 3 to 5 without converting back to ten. I heard that you can use patterns in 3 and 5 to make an equation but im not sure how to and i also heard you can use logarithms but i dont know how to use those so im kinda stumped.
Robert Dawson lui répond. |
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A camera's line of sight |
2011-02-26 |
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MJ pose la question :
A rocket that is rising vertically is being tracked by a ground level camera located 3 mi from the point of blast off when the rocket is 2 mi high its speed is 400mph At what rate is the (acute) angle between the horizontal and the camera's line of sight changing
Penny Nom lui répond. |
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At what rate is the grain pouring from the chute? |
2011-02-26 |
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MJ pose la question :
Suppose that grain pouring from a chute forms a conical heap in such a way that the height is always 2/3 the radius of the base. At the moment when the conical heap is 3 m high, its height is rising at the rate of 1/2 m/min. At what rate (in m^3/min) is the grain pouring from the chute?
Penny Nom lui répond. |
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A word problem |
2011-02-26 |
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Barb pose la question :
there are five times as many children as adult at a playground. There
are 60 people on the playground.
write an algebra equation that represents this situation. Be sure to define
your variables.(start with statement "Let X= ___")
Penny Nom lui répond. |
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A circle is inscribed inside an isosceles trapezoid |
2011-02-25 |
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priyam pose la question :
a circle is inscribed inside an isosceles trapezoid (with parallel sides
of length 18 cm and 32 cm) touching all its four sides.
find the diameter of the circle.
thanks for help!!
Penny Nom lui répond. |
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20 acres, 12 inches deep |
2011-02-24 |
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David pose la question :
How many linear yards of material is needed for a square plot of 20 acres by 12 inches deep?
Penny Nom lui répond. |
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Slicing a rectangular parallelepiped |
2011-02-23 |
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tom pose la question :
a) Pass a plane containing a vertex of a rectangular parallelepiped and a
diagonal of a face not containing that vertex to cut a pyramid from the
parallelepiped. What fraction of the volume of the parallelepiped is the
volume of the pyramid thus cut off?
b)Pass a plane through a cube of edge 8 in so that the section formed
will be a regular hexagon. Through each side of the hexagon pass two
planes, one plane containing one of the two vertices of the cube
which are farthest away from the plane of the hexagon, the other
plane containing the diagonally opposite vertex of the cube. Find the
volume of the solid bounded by these planes.
c)three of the edges of a rectangular parallelepiped that meet in a point
are also the lateral edges of a pyramid. What fraction of the parallelepiped
is this pyramid...?
you know the my only problem is how to illustrate this one...if only i
could ...can you help me....all I need is the drawing and I can do the rest
..it's fine if you'll only answer any of these but I'll be thankful if you
will do the three :)....
Penny Nom lui répond. |
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6685 is 67.5% of the total number |
2011-02-22 |
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Donna pose la question :
I know 6685 is 67.5%. How do I calculate the total number.
Penny Nom lui répond. |
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Cutting the top off a conical tent |
2011-02-22 |
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tom pose la question :
how far from the top must you cut a conical tent in order to cut the
cloth in half...
Penny Nom lui répond. |
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Triangles with perimeter 16 cm |
2011-02-22 |
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Chong pose la question :
How many triangles (up yo congruence) with perimeter 16 cm and whose lengths of its side are integers?
Chris Fisher lui répond. |
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How much gravel do I need to make it level? |
2011-02-22 |
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Robert pose la question :
I have an area that is 55 feet long x 75 feet wide and goes from 0 to 13 inches deep. How much gravel do I need to make it level?
Penny Nom lui répond. |
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