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A line through two points |
2008-09-10 |
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From Conor:
Find the equation of the straight line which passes through the points (-2,14) and (8,-1)
Answered by Penny Nom. |
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An ice cream cone |
2008-09-09 |
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From olivia:
Judy has a sugar cone and wants to know how many cubic inches of ice cream it will hold if it is filled completely to the top of the cone and no more. The cone has a height of 4.5 inches and a radius of 1.5 inches.
Answered by Penny Nom. |
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Balls and cubes in an urn |
2008-09-09 |
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From Dave:
In an urn, there are 80 objects of two kinds: cubes (C) and balls (B). An object can be either red (R) or green (G).
Note that all the four combinations are possible and that the number of cubes is not necessarily equal to the number of
balls. Similarly, the number of red objects is not necessarily equal to the number of green objects. Someone tells us that
in the urn there are 20 red cubes, 50 balls, and 30 red objects. An object is randomly selected from the urn.
(a). What is the probability that a green ball is selected?
(b). If we know that a cube has been selected, what is the probability that it's red?
(c). If we know that a red object has been selected, what is the probability that it's a cube?
Answered by Harley Weston. |
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Angle of elevation |
2008-09-09 |
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From kristy:
A man on the tenth floor of a building shouts down to a person on the street. If the angle of elevation from the street to the man in the building is 35° and the man in the building is 40 feet up, about how far away from the building is the person on the street?
Answered by Penny Nom. |
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(5x - 4) / 6 = -9 |
2008-09-09 |
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From Conor:
Solve to find x:
(5x - 4) / 6 = -9
Answered by Penny Nom. |
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Repeating fractions |
2008-09-09 |
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From Juli:
My teacher recently put my math class to the test...
We were deiscussing repeating fractions and she asked
us to find out what the bar over a repeating decimal is called. I found out
it was called the vinculum. But she also said to find out what the number
under the vinculum was called. I can't seem to find it anywhere.
Answered by Penny Nom. |
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The height of a tree |
2008-09-09 |
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From danice:
At a certain time of day, the angle of elevation of the sun is 30°. A tree has a shadow that is 25 feet long. Find the height of the tree to the nearest foot.
Answered by Penny Nom. |
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How would put .12 with 2 repeating into a fraction? |
2008-09-09 |
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From Savanna:
How would put .12 with 2 repeating in fraction?
Savanna!
Answered by Penny Nom. |
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How many ml are in 40 grams? |
2008-09-09 |
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From Nancy:
I need to know how many ml are in 40 grams. So what is the base 1ml= how may grams
Answered by Harley Weston. |
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The perimeter of a right triangle |
2008-09-09 |
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From Shanon:
I know that A=1/2bh, but for the life of me cannot figure out my 6th graders math problem.
What is the perimeter of a right triangle whose area = 600 sq. ft.
Answered by Victoria West. |
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bedmas |
2008-09-08 |
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From Jack:
i was stuck on a question 3(6-2)+3^2
Answered by Stephen La Rocque. |
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Perpendicular |
2008-09-08 |
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From amanda:
hi my name is amanda medjuck i am in grade 7. we are learning basic geometry terms and have to
define words BUT I DONT KNOW WHAT A PERPENDICULAR LINE IS PLEASE HELP ME!!!
Answered by Penny Nom. |
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0.151515...=15/99 |
2008-09-08 |
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From Emma:
This week, my Algebra teacher told us about the pattern between infinitely repeating
decimals and their corresponding fractions.
(ex. .2222222...= 2/9, .151515...=15/99, 456456456...=456/999, etc.)
I was just wondering the reason why this pattern occurs.
Is there a certain element that causes this pattern to occur?
Thanks
-Emma
Answered by Penny Nom. |
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Collinear |
2008-09-08 |
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From Patrick:
On page 17 of my son's 9th grade math book Geometry by Jurgensen, Brown, and Jurgensen (copyright 2004),
the authors state from the diagram that you can conclude the points A, B, and C are collinear.
In the diagram, the points A, B, and C appear to be situated on a straight line; however,
nothing in the diagram states that it is a straight line. I told him that you can't conclude they are collinear
because angle ABC could be 179.9 degrees instead of 180 degrees since nothing in the diagram states otherwise.
His teacher marked his answer incorrect on a test but I still believe that I am correct. How do conclude points are
collinear if nothing tells you that they are situated on a line?
Answered by Harley Weston. |
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The biggest right circular cone that can be inscribed in a sphere |
2008-09-08 |
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From astrogirl:
find the volume of the biggest right circular cone that can be inscribed in a sphere of radius a=3
Answered by Harley Weston. |
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