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Related rates |
2018-02-11 |
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From angelo:
hi admin please help me answer this question. thank you!
At a certain instant of time, the angle A of a triangle ABC is 60 degrees and increasing at the rate of 5degrees per second, the side AB is 10cm and increasing at the rate of 1cm per second, and side AC is 16cm and decreasing at the rate of 1/2 cm per second. Find the rate of change of side AB?
Answered by Penny Nom. |
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Water in a cone |
2018-02-10 |
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From Shuvo:
The diagram shows a vertical cross-section of a container in the form
of an inverted cone of height 60 cm and base radius 20 cm. The circular
base is held horizontal and uppermost. Water is pursed into the
container at a constant rate of 40 cm3/s.
Show that, when the depth of water in the container is x cm, the
volume of the water in the container is (πx^3)/27 cm3.
Find the rate of increase of "x" at the instant when "x" = 2.
Answered by Penny Nom. |
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3 yards 6 inches times 7 |
2018-02-08 |
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From Tamara:
3 yards 6 inches × 7
Answered by Penny Nom. |
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A parallelogram, a rhombus and a rectangle |
2018-02-07 |
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From Sambo:
what do parallelogram, rhombus and rectangle have in common?
Answered by Penny Nom. |
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The wholesale price given the retail price and the markup |
2018-02-07 |
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From Matthew:
Retail $99
Mark-up is 80%
What is the equation to find the original (wholesale) price (55)?
thanks
Answered by Penny Nom. |
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Adding two negatives |
2018-02-04 |
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From Pinasshakoane:
(-23)+(-3)
Answered by Penny Nom. |
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A question about perfect squares |
2018-02-04 |
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From Jolyn:
Find the smallest possible value of a whole number m if 648x m is a perfect square
Answered by Penny Nom. |
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The code on a new phone |
2018-02-02 |
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From Maria:
Hi -
My husband gave me a new Samsung Galaxy mobile for out anniversaire gift. He set me a challenge which I have to solve before I can use the Phone. He has set the pin code with numbers 4, 7 and 0 and created a four digit code with the said numbers. Is there a way I can somehow list all possible combinations and try them all? Thanks!
Answered by Penny Nom. |
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Similar rectangles |
2018-01-31 |
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From Kathy:
A rectangular picture frame is 14 inches long and 4 inches wide. Which dimensions could a similar picture frame have.
8 L X 21 W
35 L X 15 W
49 L X 14 W
7 L X 3 W
Answered by Penny Nom. |
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Positive and negative values of a function |
2018-01-30 |
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From Grayson:
f(x)=x^6-x^4
Interval: ( negative infinity, negative one )
Test Value: negative two
Function Value f(x): positive forty eight
Interval: ( negative one, zero )
Test Value: negative one
Function Value f(x): zero
Interval: ( zero, positive one )
Test Value: positive one
Function Value f(x): zero
Interval: ( positive one, positive infinity )
Test Value: positive two
Function Value f(x): positive forty eight
What is the sign of f(x) for each Interval?
Answered by Penny Nom. |
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Pricing a piece of plate steel |
2018-01-29 |
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From Simo:
I have a piece of plate that is 2500mm x 8000mm x 20mm thick and costs $7693.00
what is the formula to work out what 1000mm x 1000mm is worth?
Answered by Penny Nom. |
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Simplify 1/2^i |
2018-01-28 |
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From Deepak:
How do I simplify this complex equation:
z=1/(2^i)
Answered by Penny Nom. |
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The sum and difference of two numbers |
2018-01-25 |
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From Ali:
Hello,
I was looking at the original question that was posted and answered by
your team:
http://mathcentral.uregina.ca/QQ/database/QQ.09.07/s/donna1.html
I used the 7 and 4 as example and not looking for 39 per original
question:
A=7
B=4
7+ 4 =11 and 7-4 = 3
We end up with 11 +3 = 14
A= 14/2 give use 7
B = how do you solve for B or 4 with out knowing anything about 3 or any other numbers ?
Thank you
Ali
Answered by Penny Nom. |
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The equation of a line |
2018-01-23 |
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From Gloria:
Write the equation of a line in standard form through the point (1, 6) and perpendicular to the line 2x –y = 9.
Answered by Penny Nom. |
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y as an expression in terms of x |
2018-01-20 |
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From Mark:
What is y as an expression in terms of x ?
Answered by pennt. |
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