![](/images/transparent.gif) |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
Solve for x |
2005-07-20 |
![](/images/transparent.gif) |
From Ed: (x-1)/3 - 1 = (x + 2)/2 Answered by Penny. |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
How many tiles do I need? |
2005-07-20 |
![](/images/transparent.gif) |
From Jeannette: I am putting up backsplash tile in my kitchen and I need to know how many tiles I would need to use for about 45 square feet using 4x4 tiles. Answered by Penny Nom. |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
Three prime numbers p,q and r, all greater than 3, form an arithmetic progression: |
2005-07-18 |
![](/images/transparent.gif) |
From Ladis: Three prime numbers p,q and r, all greater than 3, form an arithmetic progression: p=p, q=p+d and r= p+2d. Prove that d is divisible by 6. Answered by Chris Fisher. |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
The equation of an ellipse |
2005-07-17 |
![](/images/transparent.gif) |
From Allan: I working on a problem that asks me to give the equation of an ellipse when only the location of the directrix and the length of the latus rectum are given. No other points on the ellipse are given. Again, the only "givens" are:
Length of latus rectum = 12
Location of directrix is x = 16
If I could determine the eccentricity, I could proceed from there by taking the ratio of the distance from a focus to the latus rectum point to the distance of the point from the directrix, but I lack the x coordinate of c. I've searched the text, and feel I've "missed something" somewhere! I note that the latus rectum segment is unique in one respect in that it is parallel to the directrix, where any other line segment on the ellipse to the focus would not be. Please indicate where I'm going wrong. Answered by Chris Fisher. |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
The area of a lot |
2005-07-17 |
![](/images/transparent.gif) |
From John: A plot of land has the following dimensions: 391 ft. x 757 ft. x 208 ft. x 788 ft. Q: How many acres is this? Answered by Harley Weston. |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
10% of $50 |
2005-07-16 |
![](/images/transparent.gif) |
From A student: If I had $50 and 10% of it had to go to my mother, how much would I have left? Answered by Penny Nom. |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
A percentage of the whole |
2005-07-16 |
![](/images/transparent.gif) |
From A student: two people both own property and would like to combine their properties into one. the first person contributes 1 acre and the second person contributes 1.5 acres. of the whole, how much percent does the first person own? Answered by Penny Nom. |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
A lighthouse is located on a small island,... |
2005-07-14 |
![](/images/transparent.gif) |
From Brittnee: A lighthouse is located on a small island, 3 km away from the nearest point P on a straight shoreline, and its light makes four revolutions per minute. How fast is the beam of light moving along the shoreline when it is 1 km from P? Answered by Penny Nom. |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
Cubic yards of topsoil |
2005-07-12 |
![](/images/transparent.gif) |
From Maggie: How much topsoil in cubic yards i need to order to cover 7500sq. ft. 3 inches deep? Answered by Penny Nom. |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
The value of n*tan*(180/n) tends to pi |
2005-07-11 |
![](/images/transparent.gif) |
From Daniel: I am 14 and i have been given a piece of maths coursework whereby a farmer has to fence off a piece of land as large as possible using 1000m of fence. I already know that the formula for working out the area of any shape of a 1000m perimeter = 5002/ n*tan*(180/n), however, after some research I have found out that as the number of sides (n), tends to infinity, the n*tan*(180/n) tends to pi. Why is this? Answered by Penny Nom. |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
A melting ice sphere |
2005-07-09 |
![](/images/transparent.gif) |
From A student: A 2 meter diameter sphere of ice melts at 1.5 millimeters per minute. How many minutes will it take to fill up a hexagonal container measuring 1.5 meters on a side, and 0.8 meters deep? Answered by Penny Nom. |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
The volume of a pool |
2005-07-09 |
![](/images/transparent.gif) |
From Douglas: I have a pond that I need to treat with an anti algae solution which needs to applied based on the volume of water in the pond (in gallons).
The rough diameter of the surface of the pond = 25 ft
The depth of the pond = 8 ft
The pond shape is conical
How many gallons of water are in my pond? Answered by Penny Nom. |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
What percent of 100,000 is 629.77? |
2005-07-08 |
![](/images/transparent.gif) |
From Someone: What percent of 100,000 is 629.77? Answered by Penny Nom. |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
Percent change |
2005-07-01 |
![](/images/transparent.gif) |
From Betty: Can you tell me the difference between Percentage Change, Percentage Increase, Percentage Difference and please give an example of each, I am very visual. Answered by Penny Nom. |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
![](/images/transparent.gif) |
The substitution method |
2005-06-28 |
![](/images/transparent.gif) |
From Addie: how do i know where to began the substitution method? how do i solve
y = x + 1
2x - y = 1 Answered by Penny Nom. |
![](/images/transparent.gif) |
![](/images/transparent.gif) |