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Sales tax |
2015-05-05 |
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From Adalyn:
Hello i've been having some trouble with math, The question is asking for a GST
and a PST
of a 30.00 dollar shirt. I don't know how to find the GST or the PST please help
Answered by Penny Nom. |
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The surface area of a hemisphere |
2015-05-05 |
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From Mandy:
How can I show that the total surface are of any solid hemisphere is 75% of the area of the full sphere?
Answered by Penny Nom. |
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The number of possible musical notes using an n-key instrument |
2015-05-04 |
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From Farihin:
Lets say that i have keys, and each key is for notes of a musical instrument,
So i wanted to find out the number of notes i can get for a certain number keys,
of course in the form of an equation. Notes can use as many keys, it can use 1, or 2, or 3, or even 100.
Notes in real life is not as such, but ignore reality.
I tried doing this but i can't seem to find a formula for it.
For example, i have 4 keys, say A, B, C, and D.
so, for notes that uses one key are 4, which is A, B, C, and D themselves.
for notes that uses two keys are 6,
AB, AC, AD, BC, BD and CD.
for notes that uses three keys are 4,
ABC, ABD, ACD and BCD.
lastly for notes that uses all four keys is 1, ABCD.
So, the total will be 4+6+4+1=15#
The nth term for the first equation is n, the second is [(n^2)-n]/2
the third and the fourth, i don't know but the final answer should be like,
n + [(n^2)-n]/2 + [3rd] + [4th]
Sorry for the long question though...
Answered by Penny Nom. |
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13 games, 3 possible outcomes |
2015-05-01 |
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From Kennedy:
Hello, hope it finds you well.
Am not that good with numbers, can you please help me get all the possible outcomes of 13 games, with a home win, draw or an away win as three possible results for each of the 13 games.
Thanks in advance
Answered by Penny Nom. |
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The method of elimination |
2015-05-01 |
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From oreanna:
Question from oreanna, a student:
How do u solve 2x+9y=3
7x-4y=-25 in elimination
Answered by Penny Nom. |
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A square and a rectangle |
2015-05-01 |
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From nick:
why is the area of a square of a given circumference greater than the area of a rectangle with the same circumference ?
Answered by Penny Nom. |
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Filling a pool with dirt |
2015-05-01 |
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From Mike:
I have a hole which a 24 ft pool in it is 10" deep in the the centre and goes to 1" inch at the edge want to fill it in with dirt how many yards of dirt would I need to fill it in
Answered by Penny Nom. |
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The volume of a sphere |
2015-04-30 |
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From Cassidy:
How do you find the radius of a sphere that has volume 36pI?
Answered by Penny Nom. |
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A fraction with a negative exponent in the denominator |
2015-04-30 |
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From ellen:
7/ab to the -4 power
Answered by Penny Nom. |
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The volume of a cube |
2015-04-30 |
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From megan:
What's the volume of a cube with a side length of 6?
Answered by Penny Nom. |
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The surface area of a cut pipe |
2015-04-27 |
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From ARUN:
dear Sir,
please advise me , how to calculate the surface area of a pipe with diameter of 630 mm and thickness of 67 mm which is cut in a angle of 22.5 degree.
please show me how to calculate the surface area of the pipe which cut in an angle.
Thanking you.
Answered by Harley Weston. |
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A five-digit pass code |
2015-04-25 |
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From Mary:
Question from Mary:
More on your published question:
I have the same type of lock, but set up a 5-digit pass code. Is that more or fewer possibilities than a 4-digit code. How many digits would make the lock most secure? I don't believe Werner specified this, but each number can only be used once. Thanks, Mary
Answered by Penny Nom. |
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A piecewise function |
2015-04-25 |
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From uday:
f(x)={x^2+3x+2 / x+2, x(not equal to)=-1
{4, x=-1
how to find domain and how the graph looks like
Answered by Penny Nom. |
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Locating the center of a circle that forms an arc |
2015-04-23 |
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From Ken:
Find the Cartesian coordinates of the center of an arc with the given location of the beginning and end points and radius length. Not the midpoint of the circumference but the actual point that the arc
is drawn around.
I know their are two answers depending on the direction of the arc. Unless we assume that all arcs are drawn counter clock wise.
Thanks
Ken
Answered by Harley Weston. |
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A word problem with fractions |
2015-04-23 |
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From Cecilia:
if one third of a pole is red, one quarter is white and 15m is black what is the height of the entire pole
Answered by Penny Nom. |
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