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The diagonal |
2001-03-28 |
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From Candace:
Building measuring 40 feet 3 inches by 50 feet 3inches What is the measurement of the diagonal of the building? What was method of obtainin answer?
Answered by Andrei Volodin. |
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Solving an equation |
2001-03-27 |
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From Jennifer:
How would I solve this equation? 1.6 = 2x/(.1-x) - the equation in parenthesises is raised to the second power. I know you take the square root of both sides, but there is where I get lost.
Answered by Leeanne Boehm. |
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12 RTV's |
2001-03-27 |
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From Christine:
- In order to promote the 2000 Census and encourage participation, 12 Road Tour Vehicles(RTV's) set out from 12 locations across the US for a 10 week promotion tour last February. The RTV's reportedly traveled a total combined distance of 97,911 miles. What was the aberage number of miles traveled in a day by each RTV?
- 2. The 12 RTV's mentioned above traveled a total combined distance equivalent to traveling 12.35 times around the earth at the equator. To the closest mile, what is the radius of the earth? Use 3.14 as your approximation for pi.
Answered by Leeanne Boehm. |
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A sugar cane crop |
2001-03-27 |
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From A student:
a sugar cane farmer harvested only 1/4 of his crop. he sold 2/3 of his harvest to the mill. what fraction of the total crop did he sell. darens recipe for florida fudge calls for 5/8 cup of sugar. if he wants to make only 1/2 of the recipe how much sugar should he use.
Answered by Penny Nom. |
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Finite non-periodical numbers |
2001-03-27 |
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From Wouter:
Is there anyone who knows the official name for decimal finite non-periodical numbers such as 0.4 or 0.25 as opposite of numbers like 0.3333333... or 0.28571428571428...?
Answered by Penny Nom. |
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Mistie, Tammy, and Jennifer |
2001-03-27 |
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From Renee:
Mistie, Tammy, and Jennifer audition for parts in a big-budget remake of Bedtime for Bonzo. On the basis of their past experience and the caliber of competition they face, Mistie has a 40% chance of being hired, Tammy has a 50% chance, and Jennifer has a 30% chance. If exactly two of the three are cast, what is the probability that Mistie was rejected?
Answered by Andrei Volodin. |
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A box with an interior of 1.25 cubic feet |
2001-03-26 |
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From Gabe:
I need a box with an interior of 1.25 cubic feet. I am using 3/4 inch material to make the box. What would the exterior dimensions be in inches?
Answered by Harley Weston. |
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66:1 |
2001-03-26 |
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From A student:
I need to know how to convert the ratio 66:1 to a percentage. I can not find an answer any where on-line when the second number is a 1.
Answered by Penny Nom. |
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Matrices |
2001-03-26 |
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From Peg:
What are some applications of matrices, basic trigonometry, and linear systems in the real world? I'm writing and Algebra report about where these topics are used outside of the classroom.
Answered by Judi McDonald and Walter Whiteley. |
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Two ferry boats |
2001-03-25 |
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From Gil:
Two ferry boats leave from opposite shores. One is faster than the other. They meet 720 yards from the nearest shore. They proceed to destination and upon returning they meet 400 yards from the other shore. What is the exact width of the river.
Answered by Penny Nom. |
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Airflow in windpipes |
2001-03-25 |
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From Ena:
The volume of air flowing in windpipes is given by V=kpR4, where k is a constant, p is the pressure difference at each end, R is the radius. The radius will decrease with increased pressure, according to the formula: Ro - R = cp, where Ro is the windpipe radius when p=0 & c is a positive constant. R is restricted such that:
0 < 0.5*Ro < R < Ro,
find the factor by which the radius of the windpipe contracts to give maximum flow?
Answered by Harley Weston. |
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Perimeter of an acre |
2001-03-24 |
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From Liz:
What is the perimeter of one acre of land?
Answered by Penny Nom. |
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Cube roots on a calculator |
2001-03-24 |
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From Will:
Hi my name is Will.I have a question about the calculator TI-83 Plus or the use of a scientific calculator. It is about using them to turn a cubed root to a decimal. When using that for a rational and irrational number. Rational numbers is a number that terminates or repeates. A irrational number goes on and on and uses ... (like pie). Like when you type the cube root of 8 it gives you 2, and that is a rational number. The squre root of 2 is 1.41421356... that is irrational. So why is it when you put the cube root of 16 in the calculator it says 2.5198421 that is rational it terminates at the ninth digit and my float is set for the tenth? But why when you do it by hand you get the 2 times the cube root of 2 and that is irrational? Why is that?
Answered by Judi McDonald. |
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An elliptic tunnel |
2001-03-24 |
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From Janna:
A tunnel is built under a river for a road 12m wide with a 2m sidewalk on either side. The top of the tunnel is semi-elliptical. A local bylaw stipulates that there must be a clearance of at least 3.6m at all points on the road. If the smallest possible ellipse is used, find the clearance at the center of the road.
Answered by Harley Weston. |
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A suspension bridge |
2001-03-24 |
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From Janna:
The cables of a suspension bridge hang in a curve which approximates a parabola. The road bed passed through the vertex. If the supporting towers are 720m apart and 60m high, find: a) an equation of the parabola (it's y = 1/2160x2) b)the height of the cables at a point 30m from the vertex. I substituted 30 in for the x value and got 0.42 and the answer is 42. What did I do wrong?
Answered by Denis Hanson and Claude Tardif. |
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