







Covering a ceiling with tablecloths 
20170224 

From DEANNA: I am trying to cover a 16 x 31 foot ceiling with tablecloths. For sale, are 90 x 132 inch tablecloths for $4.97 a piece and 60 x 102 inch tablecloths for $3.85 a piece. Which would be my cheapest option to cover the entire space? Answered by Penny Nom. 





A puzzle embedded in a table top 
20160513 

From Aaron: I want to make a table with a puzzle embedded in it. The table top would be a
36" circle and the puzzle is 20"x27" I'm thinking that it's not going to fit,
but not sure. Any help would be appreciated.
Thanks,
Aaron Answered by Penny Nom. 





Countable and uncountable sets? 
20160115 

From wilson: what are the countable and uncountable sets? Answered by Penny Nom. 





An input/output table 
20150113 

From Rose: How do you create an input/output table when the rule is: the output is a +5? Answered by Harley Weston. 





An input output table 
20140419 

From Stephanie: I have an input output table with x/y filled out except one x and one y. I need help. How do I find X? Answered by Penny Nom. 





A table of values 
20140327 

From Marisol: A table value X 0,1,2,3,4,5,6 and Y 3,7,11,15,19,23,27 . what relationship of X to Y is represent by which equation? A . y= 4x. B y =x+3 . C y =4x+3 or . D y =4x3 Answered by Penny Nom. 





Matrices 
20131110 

From Ricky: Why must we have brackets around matrices. Why don't we just neatly write an array of entries crosswise and up and down to indicate a particular matrix? Answered by Chris Fisher. 





A chart for y=mx+b 
20130311 

From jacinda: how to make a chart for y=mx+b Answered by Penny Nom. 





The multiplication table for the different bases 
20130201 

From sylvia: I am having a difficult time trying to figure out how to fill in the multiplication table for the different bases. i don't know how to get the numbers. Answered by Penny Nom. 





An inputoutput table 
20100607 

From Brian: Make an Input output table to represent the function. Use 0,1,2,3 as the Domain.
f(x)= 3+7x Answered by Harley Weston. 





A table of values 
20100422 

From Donna: Complete the table by determining the value of each letter. Explain what rule is used to relate the numbers in the second column (with the heading of y) with those in the first column (with the heading of x).
x  y
3  5
9  23
4  8
6  A
7  B
C  11
D  2
I can't figure this out, can you help me? Answered by Robert Dawson. 





y=2x+1 and y=2x1 
20090828 

From MARICELA: Need help of how to work this problems
y=2x+1 and y=2x1
First of all what is the difference?
Second I think is easy just to work with the X y with the line in the middle
but how do you get the numbers for each side. Answered by Penny Nom. 





The axiom of choice and constructibe sets 
20090410 

From sydney: The axiom of choice asserts the existence of certain sets, but does not construct the set. What does "construct" mean here? For example, does it require showing the existence and uniqueness of some function yielding the set? In general, what does it mean to require the existence of a mathematical object be tied to a construction of it? Answered by Claude Tardif. 





A slopped table top 
20090316 

From anthony: A perfect circle with radius 100m is supported by four legs, 50m long. The circle is flat when all four legs are 50m long, and tilted when the legs are different in length. The four legs are spread evenly 90 degrees apart at 0, 90, 180, and 270. Find the high and low points in degree and height when the legs are 55m at 0 degree, 70m at 90 degree, 45m at 180 degree, and 30m at 270 degree.
Not sure if they can be calculated using only 2 or 3 legs.
I have tried by picking the two adjacent highest legs (55m and 70m) so I know the high point falls into the first quadrant. Then I tried using ratio to determine where the high point is, which I think high point should be closer to the 70m leg, I am not sure. If I can find the high point, the low point should be opposite to it. Answered by Chris Fisher and Harley Weston. 





An octagonal poker table 
20090223 

From Corey: I'd like to build an octagonal poker table using 4'x8' sheets of plywood. I would like each side edge to be approx. 2' wide. I am sure that due to the angles I can do this with one sheet of plywood, but i don't know how to measure for this. Can you help? Answered by Robert Dawson and Harley Weston. 





Seating around a circular table 
20090209 

From Jenny: A committee of 15  9 women and 6 men  is to be seated at a circular table (with 15 seats). In how many ways can the seats be assigned so that no two men are seated next to each other? Answered by Victoria West. 





The circumference of a table 
20090114 

From Maggie: My dinning room table is 48 inches. I need to know what its Circumference is?
I do not know algebra so a formula will not help me. Answered by Penny Nom. 





The table of values for y=3x10 
20090109 

From Jade: How can I know the value of x for y=3x10 in this table of values pls. include the deatails
if x=2 y=16
if x=3 y=1
but how if y=2 what is x Answered by Penny Nom. 





Compatible numbers 
20081030 

From Paul: Use compatible numbers to estimate the quotient of 23.52 and 11.04 Answered by Penny Nom. 





Escort cards on a rectangular table 
20080613 

From Susan: What size rectangular table will we need to put 230 2" X 3.5" escort cards on for my daughter's wedding reception with a spacing of .5 inch between them on all sides? Thanks so much for your help Answered by Penny Nom. 





Rectangular cards on a round table 
20080611 

From Susan: How many 4" X 3.5" wide escort cards will fit on a 48" diameter table. These are for my daughters wedding. I have already added the extra spacing between the cards into the size of the cards.Thanks for your help Answered by Janice Cotcher and Harley Weston. 





Saving to buy a coat 
20080309 

From alayna: Jackie is saving her money to buy a coat that costs $121. If she already has $61 and saves
$15 each week, in how many weeks can she buy the coat ? Make a function table to answer the
question. Answered by Penny Nom. 





Cantor's diagonal argument 
20080126 

From David: Cantor's theory using a diagonal across a list of real numbers to proven uncoutability has always puzzled me.First in base ten, it feels like hocus pocus so I began thinking of the Boolean numbers as truer representations of place value (on,off). Secondly his list was always arbitrary or so I recollect. Therefore, I suggested using a seriesA=.10000....,B=.01000. C=.11000, etc.
Any diagonal is already located among the numbers listed. My only alteration is that since the final digit is always unrepresentably either one or zero, but it must be one or the other, I make an assumption that if x= .abc...1 and y= .abc...2 the only two possibilities and I choose to count F=x+y then then the numbers are countable= Z=sumFi,where I=2+2^2+2^3...
I hope this sketch is enough description, I asked Rudy Rucker more formally but got no mathematical response, someone else gave me some tale about slippery epsilon. What do tyou think of recasting his proofs in more rigorous form?
David French Answered by Claude Tardif and Walter Whiteley. 





A circular table is pushed into the corner 
20071031 

From Will: A circular table is pushed into the corner of a square room so that one point is 8 inches from one wall and 9 inches from the other. What is the radius of the table? Answered by Penny Nom. 





An octagonal table 
20071018 

From Lorne: I am 77 years old and want to build a table top with each side measuring 23 inches.
I believe the diameter would be 55.5 inches. Is this correct and what is the angle of the cuts I have to make? Thank you for your patience. Answered by Penny Nom. 





More on the cardinality of sets 
20070727 

From Mac: Can you please help me to find and verify whether the following are
finite, countably infinite and uncountable ? Answered by Harley Weston. 





Countable and uncountable sets 
20070724 

From Mac: Hi, i tried to read few webpages related to the countably infinite and uncountable sets.
Even i read few questions from this forum.
But i am not convinced with this explanation. If you have any good book that
explains this in layman term, please redirect me to that.
1) Can you please explain what is the difference between these too ?
2) How could you say set of Natural number and set of even numbers are countably
infinite ?
N={1,2,3,...} and Even= {2,4,6,...}
When an element in the even set is some 2n, we will map it to 'n'.So
now we have a bigger number(2n) right ?
Sorry, i didn't understand that.
...
Can you please help me out to understand that ? Answered by Harley Weston. 





Countable and uncountable sets 
20070213 

From piyush: we se that union of countably infinite no of sets having countably infinite number of elements is a countable set we can express p(n) (i.e power set of natural number) as a union of countable infinite number of sets i.e p(n)=s1Us2Us3..... where s1=null s2={1,2,3,4,5..........} s3={{1,1},{1,2},{1,3},..............{2,1},{2,2}........} using the same statement can we prove that power set of natural number is a infinit countable set Answered by Penny Nom and Claude Tardif. 





Inputoutput table 
20070110 

From Richard: Question is make an input  output table for the function using the domain 0,1,2,3,4, Then state the range of the function.
y =x + 8 ?
y =0.4x +3 ? Answered by Penny Nom. 





The real numbers with decimal representations consisting of all 1s. 
20061029 

From Ivessa: Determine if the following set is countable or uncountable : the real numbers with decimal representations consisting of all 1s. Answered by Steve La Rocque and Walter Whiteley. 





Mastering the multiplication tables 
20060404 

From Ellie: I need a detailed study plan fro helping my son master his multiplication tables.
Grade: 3 elementary Answered by Paul Betts. 





A table of values 
20060328 

From Cindy: Create a table of values for each of the following functions: y=5x, y=52, and y=5x. I dont know to do this. Answered by Stephen La Rocque. 





The cartesian product of a countably infinite collection of countably infinite sets 
20060325 

From Geetha: Is the cartesian product of a countably infinite collection of countably infinite sets countable infinite? Answered by Penny Nom. 





What percentage of the seniors polled yes? 
20060320 

From Jean: An equal number of juniors and seniors responded to the question, "Do you like math?" Each respondent said yes or no. If 70% of those who said yes were seniors and 80% of those who said no were juniors, what percentage of the seniors polled yes? Answered by Penny Nom. 





How long and how wide is the table? 
20060202 

From A student: the perimeter of a table is 24 feet. the table is twice as long as it is wide. how long and how wide is the table? Answered by Penny Nom. 





Complete the array 
20051211 

From Ginger:
Make the sum of these number add up to six.
Going across, down, corner to corner. Using the number 4, 2, 0 only.
Answered by Penny Nom. 





Quadratics 
20050105 

From Usman: Hi, in my Grade 11 Functions math class we have been assigned the task of finding jobs and careers related to quadratics, I have done many searches but have been unsuccessful, then I saw your website and emailed. I also have to use an example of a math problem that the job uses, then solve it, this will all compile on bristol board for a presentation. I would greatly appreciate it if you could send me some links and references of sources that refer to this subject. Answered by Harley Weston. 





An elliptical table 
20050103 

From Roger: Want to make an elliptical table, say the long (major) axis is 4 feet, and the short (minor) axis is 3 feet. I can construct this figure, but I'm trying to figure out what the exact dimension of a rectangle within this ellipse will be if I make the table a drop leaf type where the drop dimensions are equal for each end of both the long and short axes. Intuitively, it looks like there is one and only one solution. Answered by Penny Nom. 





ChiSquared 
20040505 

From Gillian: OF75 PEOPLE, 43 ARE EXPOSED TO A VIRUS AND BECOME ILL. 11 PEOPLE ARE EXPOSED AND DO NOT BECOME ILL. 3 PEOPLE ARE NOT EXPOSED AND BECOME ILL. 18 PEOPLE ARE NOT EXPOSED AND DO NOT BECOME ILL. THE ATTACK RATE IS 80% FOR THOSE EXPOSED AND 14% FOR THOSE NOT EXPOSED. THE RELATIVE RISK IS 5.7. CAN YOU EXPLAIN TO ME HOW TO CALCULATE A CHI SQUARE TEST FROM THIS. Answered by Penny Nom. 





Arrangements around a circular table 
20031007 

From Lori: How many arrangements can 6 people be seated round a circular table? Answered by Penny Nom. 





The base 10 multipliction table 
20020707 

From A student: These are two questions from Math for Elementary Teachers and they have me stumped. You have two coins that are worth 30 cents. One of the coins is not a nickel. What are the two coins? The product of the diagonals of any 2x2 matrix in the base 10 multiplication table are equal. Why? Answered by Penny Nom. 





Cardinality of sets 
20011119 

From Tania:
 Show that the cardinality of P(X) (the power set of X) is equal to the cardinality of the set of all functions from X into {0,1}.
 Show that (the cardinality of the natural numbers set) N = NxNxN.
 Show that the cardinality of the set of prime numbers is the same as the cardinality of N+
Answered by Walter Whiteley. 





Subsets of a countably infinite set 
20011114 

From Tania: How could I show (and explain to my son) that any countably infinite set has uncontably many infinite subsets of which any two have only a finite number of elements in common? Answered by Claude Tardif. 





Logic and Matrix Instruction 
19980424 

From Robin Booker: I need assistance with instruction strategies to teach the construction of a matrix, solving a logic problem. Providing instruction in the construction of a simple matrix , no problem. However, I stumpted on this one. Five players were chosen as All Stars at the basketball banquet. Based on the following clues, find the player's name, team, uniform color and number of points scored.... Answered by Harley Weston. 





Les tableaux de conversions 
20010503 

From JeanJacques: Sur quel site est il possible de trouver tous les tableaux de conversions de mètres,kg,litre,m2,m3 Quelle est la relation entre les m^{3} et les litres 1 m^{3} = 1000 litres = 1000 kg? Answered by Claude Tardif. 

