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Weighing a 1000 lb cylinder on a 500 lb scale |
2010-05-28 |
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Jerry pose la question :
I am trying to weigh a large possibly 1000 lb cylinder on a 500 lb scale, is this possible? If so what is the actual formula to figure out the correct weight? I am told it is possible with the fulcrum method but have not been able to find a formula. Thanks Jerry
Robert Dawson lui répond. |
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More on a truncated cone |
2010-05-28 |
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Mike pose la question :
Question from Mike, a parent:
I was reviewing this question and answer:
http://mathcentral.uregina.ca/QQ/database/QQ.02.06/phil1.html
But I have trouble with this part:
Now if we express the radius of the inside circle as r and the outside circle's radius is R, then this means r/R is 911/1728. But earlier we said that the outside radius R is simply w more than the inside radius r, so R = r + 282. That means that r/R = r/(r + 282). Now we can simply solve the equation for r:
r/(r+282) = 911/1728
This means r = 314 mm (with rounding).
Can I get more detail on the method to solve for r?
Thank you,
Mike
Penny Nom lui répond. |
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Odd integers |
2010-05-28 |
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jack pose la question :
If x is an odd integer, which of the following must also be an odd integers
a) x+1; b) 2x; c) x+4; d) x-1; e) x/2? Please help me to solve this problem. Thank you.
Penny Nom lui répond. |
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Two problems |
2010-05-27 |
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debbie pose la question :
Question from debbie, a parent:
hi, i have a daughter and she asked me a maths question I cannot solve. I was just wondering if you can give me the answers plus the working out so I could explain to my daughter,
1. The leftmost digit of a six-digit number N is 1. If this digit is removed and then written as a rightmost digit, the number thus obtained is three times N .Find N.
2. Four friends are racing together down a flight of stairs. A goes 2 steps at a time, B 3 steps at a time. C 4 steps at a time and D 5 steps at a time. The only steps which all four tread on are the top one and the bottom one. How many stairs in the flight were stepped on exactly once?
Penny Nom lui répond. |
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A comparative report |
2010-05-27 |
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jo pose la question :
Question from jo:
I have a comparative report and I was confused about how to get the percentage of the current 1st quarter vs. last year 1st quarter, vs. last year of the same month. I hope you could help me, thank you.
Example: Food sales: 3Day Sale Event
TY: 1,352,293.58 May (Back to School)
LY: 1,205,614.31 April (Summer Sale)
LY: 1,065,693.40 May 2009
Penny Nom lui répond. |
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More on carbon 14 dating |
2010-05-26 |
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Malachi pose la question :
I am doing carbon 14 dating and i figured out the rule for taking the percent of the original C-14 to figure out how old it is. how do I work the equation the other way around to find the percent remaining, from how long ago the objects organic mater died
Harley Weston lui répond. |
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Graphing a linear inequality |
2010-05-26 |
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Valeie pose la question :
When graphing a linear inequality, how do you know if the inequality represents the area above the line.
Penny Nom lui répond. |
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Liquid in a horizontal tank |
2010-05-26 |
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Brian pose la question :
I have a 50' long tank by 12' diameter it is lying down on it side with 12" of Liquid in the bottom i need to know how many gallons of fluid this is? Please Help, I was able to calculate out the Triangle but not the Sector!
Harley Weston lui répond. |
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A square pyramid |
2010-05-26 |
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Georgia pose la question :
Question from Georgia, a student:
I have been given the following question in a maths assingment, and have so far been unable to answer it.
To begin, i am required to draw a square pyramid as follows:
1. draw a 3 dimensional diagram of a square based pyramid
2. label the square base as ABCD, call the vertex H.
3. Mark in E and F the midpoints of AD and BC respectively and O is the midpoint of EF
Note: this therefore makes FO = FC
this i was fine with, it was the following question that stumped me.
1. if the height of the pyramid is 280m, what is the length of the base?
Thanks, Georgia
Chris Fisher lui répond. |
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A square inscribed in a circle |
2010-05-25 |
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Middle pose la question :
what is the perimeter of a square inscribed in a circle of radius 5.0 inches?
Penny Nom lui répond. |
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What is the speed of the current? |
2010-05-25 |
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tien pose la question :
a boat travels upstream, against a current, at a speed of 4 miles per hour. On the return trip, the boat travels downstream, with the current , at 10 miles per hour. the speed of the current remains constant. what is the speed of the current?
Penny Nom lui répond. |
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How wide a strip has he cut when the lawn is half mowed? |
2010-05-24 |
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Arib pose la question :
rectangular lawn has length 40 m and width 30 m. David starts cutting from the outside in. How wide a strip has he cut when the lawn is half mowed?
Penny Nom lui répond. |
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What is the distance from A to C via B? |
2010-05-24 |
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vivianne pose la question :
The distance from A to B is d km and that from B to C is x km. if a bus maintains an average speed of 50km/hr between A and B and 60km/hr between B and C, it takes 3 hours to travel from A to C. If it maintains 60km/hr between A and B and 50km/hr between B and C, the journey takes 8 minutes less. What is the distance from A to C via B?
Penny Nom lui répond. |
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Math in the workplace: nursing |
2010-05-24 |
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Taylor pose la question :
How is math used in the workplace - Nurse Anesthetist?
Penny Nom lui répond. |
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An optimization problem |
2010-05-23 |
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Marina pose la question :
Hello, I have an optimization homework assignment and this question has me stumped..I don't even know A hiker finds herself in a forest 2 km from a long straight road. She wants to walk to her cabin 10 km away and also 2 km from the road. She can walk 8km/hr on the road but only 3km/hr in the forest. She decides to walk thru the forest to the road, along the road, and again thru the forest to her cabin. What angle theta would minimize the total time required for her to reach her cabin?
I'll do my best to copy the diagram here:
10km
Hiker_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _Cabin
\ | /
\ | /
f \ 2km /
\ | /
theta \___________________________ /
Road
Penny Nom lui répond. |
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