







Two problems 
20100527 

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 sixdigit 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. 





Adding five positive integers that have a product of 48 
20100427 

Lorraine pose la question : What is the smallest possible sum that can be obtained by adding five positive integers that have a product of 48. Chris Fisher lui répond. 





Dividing seashells among girls 
20100106 

Eileen pose la question : A group of girls collected some seashells from the beach. They tried to divided these seashells equally among them. If each girl received 8 seashells, they would need 5 more seashells. If each girl received 7 seashells, they would have 3 seashells extra. How many seashells did they collect from the beach altogether? Robert Dawson and Penny Nom lui répond. 





Dividing a number which is greater than 1 by a number that is less than 1 
20100105 

Neda pose la question : when dividing a number which is greater than 1 by a number that is less than 1, will the quotient be greater than or less than the dividend? Explain. Robert Dawson and Penny Nom lui répond. 





How many students were there 
20090125 

sooos pose la question : After a math lecture in university, the students go to the cafeteria. EACH ONE of them buys a cheese sandwich and a cup of tea. They ALL pay $18.49. How many students were they? Chris Fisher lui répond. 





The factors of an integer 
20090106 

Madison pose la question : what are the factors of 878 Robert Dawson lui répond. 





Do all square numbers have an odd number or factors? 
20081211 

Amy pose la question : Do all square numbers have an odd number or factors? Victoria West lui répond. 





A remainder of 8 
20081023 

Kathy pose la question : When dividing a 3 digit number by a 1 digit number, for what divisors can you get a remainder of 8? is the question in my son's math book. After searching this web site, how do you explain an answer so that a ten year old can understand? I somewhat understand the answers given, but am afraid my son might not understand the answer? Help??? Penny Nom lui répond. 





Number of factors 
20080918 

Austin pose la question : I am stuck on finding what type of number has exactly two factors and
what type of number has an odd number of factors? I need some examples. Penny Nom lui répond. 





Number of factors 
20080720 

pete pose la question : how do you find the number of factors in a really big number without using a factoring program or listing the out? Penny Nom lui répond. 





How many positive integer factors of 2^2*3^2*5 are multiples of 12? 
20080627 

Peter pose la question : How many positive integer factors of 2^2*3^2*5 are multiples of 12 Janice Cotcher lui répond. 





Find the smallest number that leaves a remainder of 10 when divided into 90. 
20080624 

Peter pose la question : Find the smallest number that leaves a remainder of 10 when divided into 90. Janice Cotcher lui répond. 





What number has exactly 51 divisors? 
20080226 

Lisa pose la question : What number has a Tau which equals 51? In other words, what number has exactly 51 divisors? It must be a square of some kind! Penny Nom, Victoria West and Harley Weston lui répond. 





Positive divisors 
20071126 

joan pose la question : How many positive divisors of ((2^20)*(5^20))^2 are less than (2^20)*(5^20) but do not divide (2^20)*(5^20)? Victoria West lui répond. 





What are the factors of 111? 
20070913 

Miska pose la question : What are the factors of 111? Penny Nom lui répond. 





How many stairs in the flight are stepped on exactly once? 
20070903 

Bill pose la question : Four friends are racing together down a long flight of stairs. A goes 2 steps at a time, B 3 at a time, C 4 at atime and D 5 and at a time. The only steps on which all four tread are the top one and the bottom one. How many stairs in the flight are stepped on exactly once. Harley Weston lui répond. 





An odd number with 12 factors 
20070627 

Wilson pose la question : Do you know of any odd number that has 12 factors? Reply back today.
Because I have hand in a project tomorrow. Stephen La Rocque and Harley Weston lui répond. 





Find the divisors 
20060821 

Minh pose la question : Using combination or permutation or both, find the
a. Divisors
b.even divisors
of 2160 Stephen La Rocque and Penny Nom lui répond. 





When 391758 and 394915 are divided by a certain three digit number, ... 
20060726 

Nick pose la question : When 391758 and 394915 are divided by a certain three digit number, the three digit reminder is the same in each case. Find the divisor. Chris Fisher and Steve La Rocque lui répond. 





x^2+2x3 is a factor f(x)=x^4+2x^37x^2+ax+b 
20060406 

Maha pose la question : Given that x^{2}+2x3 is a factor f(x)=x^{4}+2x^{3}7x^{2}+ax+b, find a and b and hence factor f(x) completely. Penny Nom lui répond. 





given that p is a prime and pa^n, prove that p^na^n 
20060324 

Janna pose la question : given that p is a prime and pa^{n}, prove that p^{n}a^{n} Stephen La Rocque lui répond. 





How many divisors does the number 138600 have? 
20060208 

Joe pose la question : How many divisors does the number 138600 have? Steve La Rocque and Penny Nom lui répond. 





For what divisors can you get a remainder of 8? 
20060106 

Thelma pose la question : When dividing a 3 digit number by a 1 digit number, for what divisors can you get a remainder of 8? Penny Nom lui répond. 





Numbers with exactly 5 divisors 
20051123 

Mary Lou pose la question : Show the 10 numbers with exactly 5 divisors. Penny Nom lui répond. 





n^2+n1 has no divisors ending with 3 or 7 
20050908 

Arne pose la question : at least it seems like for any integers n and k,
10k+3 and 10k+7 do not divide n²+n1
I tested this for every n from 0 to 3200 (which means same for the numbers from 3201 to 1)
could this be true, or is it just coincidence, or am I just totally wrong? Richard McIntosh lui répond. 





Some numbers less than 100 
20040917 

Paul pose la question : for how many numbers less than 100 is the digit in the ones place half the digit in the tens place? Penny Nom lui répond. 





Crossword math puzzle 
20040914 

Joyce and Tiffany pose la question : The puzzle name was real number vocabulary and the question is (a number that divides evenly into another what is it?). (Space in between ticmarks on a number line). Harley Weston lui répond. 





an integer with three factors 
20040803 

A student pose la question : What is the probability that a randomly chosen 3 digit number has exactly 3 factors Penny Nom lui répond. 





Divisors of 2n+1 and 3n+9 
20040602 

Chris pose la question : Amy selected a positive integer N and wrote numbers 2xN+1 and 3xN+9 on a whiteboard. Boris looked at the two numbers on the whiteboard and wrote in his notebook a positive integer that divides each of them. Find all possible numbers that Boris could have written in his notebook. Chris Fisher and Penny Nom lui répond. 





What is a number that has exactly 13 factors? 
20031109 

Mary pose la question : What is a number that has exactly 13 factors? Penny Nom lui répond. 





Which one has the most factors? 
20031031 

Kristi pose la question : Of all the whole numbers less than or equal to 5000, which one has the most factors? Claude Tardif lui répond. 





1/x + 1/y = 5/12 
20031030 

Ben pose la question : 1/x +1/y =5/12, what is the sum of x and y? Penny Nom lui répond. 





Relatively prime 
20030927 

James pose la question : what is the definition a relative prime numbers? Penny Nom lui répond. 





Division names 
20030310 

A parent pose la question : what is the answer to a division problem called Penny Nom lui répond. 





(n+17)(n+7) = 0 
20030305 

Janea pose la question :
What is the answer to 1. (n+17)(n+7)=0 What is the answer to:2. (y15)(y100)=0 Penny Nom lui répond. 





Multiples of all four of the numbers 2, 3, 4, and 5 
20030211 

Stephanie pose la question : How many of the first 1000 positive integers are multiples of all four of the numbers 2, 3, 4, and 5? Penny Nom lui répond. 





Composites, primes, factors and common factors 
20021120 

Connie pose la question : My son can't remember what a composite number is, what a prime number is and the explaination of factors and common factors. Help! Penny Nom lui répond. 





Find the two numbers 
20010221 

A grade 6 student pose la question : Find the two numbers: 5 is a common factor; 100 is a common multiple; neither number is a mulitple of the other; both are even. Penny Nom lui répond. 





What number from 1 to 25 has the most factors? 
20010123 

John pose la question : What number from 1 to 25 has the most factors? Penny Nom lui répond. 





A pair of numbers whose GCF is 28 
20001227 

John pose la question : Name 2 different pairs of numbers whose GCF is 28. Penny Nom lui répond. 





Dividing with decimals 
20001115 

Alex pose la question : I teach math and my class and I were discussing the dividing of decimals. I explained that if there is a decimal in the divisor, it needs to be moved and so does the decimal in the dividend. My question is why is it necessary to move the decimal point in the divisor before dividing? Penny Nom lui répond. 





Divisors of 2000 
20000606 

Amanda Semi pose la question :
 find the product of all the divisors of 2000
 dog trainer time has 100m of fencing to enclose a rectangular exercise yard. One side of the yard can include all or part of one side of his building. iff the side of his building is 30 m, determine the maximum area he can enclose
Claude Tardif lui répond. 





Factors 
20000127 

Pam pose la question : My son [age 9, 4th grade] has a math problem with factors. I need to know how to do the problem that involves the factor 24. I'm not even sure where to start. Harley Weston lui répond. 





Two algebra problems 
19991217 

Michael Standfest pose la question : If x+4 is a factor of 2x^{4}+kx^{3}3kx^{2}+6x40, find k and Prove that n^{2}n is even for all n, using the proof of contradiction Penny Nom lui répond. 





An odd number of factors 
19991022 

Melissa pose la question : What is the common name used for numbers that have an odd number of factors? What is the least positive integer that has exactly 13 factors? Penny Nom lui répond. 





Tshirts 
19990404 

Valerie pose la question : At a discount Tshirt shop the manager marked a special batch of Tshirts that originally sold for $2.00. When all the shirts sold the shop had collected $603.77. How many shirts did they sell and what was the price per shirt? Jack LeSage and Penny Nom lui répond. 





Pick any odd number, square it, and then divide it by 8 
19981127 

Brenda Meagher pose la question : Pick any odd number, square it, and then divide it by 8. No matter what odd number is chosen and squared and divided by 8, the remainder is one. Could you please explain this to me or is there a pattern that I am not aware Harley Weston lui répond. 





Composite Numbers 
19981007 

Greg Murphy pose la question : What type of composite number has an odd number of factors? Harley Weston lui répond. 





Students and Lockers 
19981002 

Mike pose la question : There is a row of 1000 lockers. There is a line of 1000 students. Student number 1 starts at the first locker and opens all 1000. Student number 2 starts at the second locker and closes every other one. Student number 3 starts at the third locker and goes to every third one, closing the open ones and opening the closed ones. Student number 4 does the same with every fourth locker and so on down the line... After all 1000 students have gone how many lockers are open and which ones are they? Please help! There is proboly a simple solution but we couldnt figure it out for the life of us. Please let us know how you solve it. Patrick Maidorn and Penny Nom lui répond. 





Five Factors 
19980919 

Derek Yau pose la question : To whom it may concern, I have difficulty in getting the solution to the following question: Find 5 numbers that have exactly 5 factors. I got 16, 81 but couldn't find the rest. I believe that in order to have 5 factors, it has to be a square number. Isn't it true? I guess there may be a pattern to this. Thanks for your help. Derek Yau. Penny Nom lui répond. 





A divisor. 
19980905 

Kim Tangney pose la question : When 391 758 and 394 915 are divided by a certain three digit numbers, the three digit remainder is the same in each case. Find the divisor. Penny Nom lui répond. 





Divisors of 6n 
19980126 

James pose la question : If n is a positive integer such that 2n has 28 positive divisors and 3n has 30 positive divisors, then how many positive divisors does 6n have? (a) 32 (b) 34 (c) 35 (d) 36 (e) 38 Penny Nom and Haragauri Gupta lui répond. 





Number of factors 
19960130 

Chrissy pose la question : What number has exactly 13 positive factors? Penny Nom lui répond. 

