Math Central - mathcentral.uregina.ca
Quandaries & Queries
Q & Q
. .
Fresh off the press   Here are the newest items
added to Quandaries & Queries:
. .
start over

A poorly worded question 2014-10-14
From Marjorie:
How do I figure out the following? Dylan's dog weights 12 times more than his pet rabbit. The dog and the rabbit weight 104 pounds. How much does Dylan's dog weigh? Would you explain in detail how I would arrive at the answer so I can convey same to my grandson who is in the 5th grade. Thanks.
Answered by Penny Nom.
A linear system 2014-10-14
From pheter:
4/x - 1/y = 3 .... equation (1)
6/x - 2/y = 5 .... equation (2)

Answered by Penny Nom.
A fact family containing 4, 4 and 16 2014-10-14
From Leslie:
I am helping my son and the question is 4,4,16 in fact family what does that mean
Answered by Penny Nom.
How does pir^2 = 1/4pid^2? 2014-10-14
From al:
Hi I cant work out the algebra. How does pir^2 = 1/4pid^2 Thanx
Answered by Penny Nom.
Building an 8 sided box 2014-10-14
From Michael:
I want to build an 8 sided box. The North, East, South, and West sides I want them to be 4 feet in length.
The NE, SE, SW, and NW sides I want to be 2 feet in length. What angles do I need to cut my angles.
Thanks Michael

Answered by Penny Nom.
15 - (5-x)/ x = 30 2014-10-13
15 - (5-x)/ x = 30

I thought you had to multiply both sides by x in order to remove the fraction?

15x - 5x - x2 = 30x

then combine 10x - x2 = 30x

-x2 =20x

then take the sqrt of each side...

what am I doing wrong??

Answered by Penny Nom.
Pre algebra 2014-10-12
From mohamed:
i want to know the meaning of pre algebra
Answered by Penny Nom.
A quarter mile row of trees 2014-10-09
From junna:
a farmer would like to plant trees on one side of his lot which is 1/4 of a mile in a length His friend advised him that if he would plant the trees 5 feet farther apart,he would need 44 fewer trees.If the farmer would take the advice, how many trees would he plant?
Answered by Penny Nom.
Why express fractions in lowest terms? 2014-10-09
From John:
I teach in a Faculty of Education. A colleague in the university asked me about fractions and lowest terms. I am quoting the person below, and would appreciate your insights into the question/thought.

"One I'm struggling with is why (for example) 6/18 is not considered as good an answer to a fraction question as 1/3. The traditional response is that 6/18 is not in lowest terms so the question has not been finished until the fraction is reduced, but what actually makes the lowest terms answer the better one? Is it convention? Is there a way to explain why simplest form answers in fractions are right and and anything else is considered incorrect without alluding to some need for this 'good habit' elsewhere in math or science? Is there a real-life reason?" Thank you for any insights and if you have nothing to offer to this query, that is fine too. I appreciate your consideration. John

Answered by Robert Dawson.
A 20% markup 2014-10-09
From Fatima:
What is the 20% markup price of $1.50
Answered by Penny Nom.
Maximizing the ticket revenue 2014-10-07
From Allen:
An airplane whose capacity is 100 passengers is to be chartered for a flight to Europe. The fare is to be $150 per person, if 60 people buy tickets. However, the airline agrees to reduce the fare for every passenger by $1 for each additional ticket sold. How many tickets should be sold to maximize the ticket revenue for this flight?
Answered by Chris Fisher.
One zero to a quadratic expression 2014-10-06
From Kevin:
Find a value of n such that f(x) = 3^x2 + nx + 6 only has one zero, is this the only solution to the question?
Answered by Penny Nom.
A tennis ball in a triangular prism 2014-10-06
From Anna:
Hi, I need to find the the base and the height of a triangular prism, but I only know the diameter of a tennis ball that fits exactly in the triangular container.. The diameter for the ball is 8.50cm. Can you help me find the formula? Thank you!
Answered by Penny Nom.
A factoring problem 2014-10-05
From Gina:
Answered by Penny Nom.
Sieve of Eratosthenes 2014-10-03
From Hope:
using Sieve of Eratosthenes to determine for in instance prime numbers between 1 to 200, to what nth number should i stop?, 4th, which is 11 or what?
Answered by Robert Dawson.



Math Central is supported by the University of Regina and The Pacific Institute for the Mathematical Sciences.



Home Resource Room Home Resource Room Quandaries and Queries Mathematics with a Human Face About Math Central Problem of the Month Math Beyond School Outreach Activities Teacher's Bulletin Board Canadian Mathematical Society University of Regina PIMS