Centrale des maths - centraledesmaths.uregina.ca
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 calcul des hh,mn,sec 2008-01-19 gillot pose la question :bonjour, mon fils à des additions et soustractions d'horaire et je n'arrive pas à trouver la règle pour lui espliquer comment il faut faire il y a t il une formule pour les additions et soustractions merci par avance pour vos réponsesClaude Tardif lui répond. A=B+C+D+F+G+H+J 2007-11-27 Boubendir pose la question :voila ma question et comme savoir les nombres additioné en etulisant le resultat A=B+C+D+F+G+H+J au debut ons a les B,C,D,F,G,H,J on connaissent leur valeur comment retrouver valeur on etulisant leur resultatClaude Tardif lui répond. Gauss' Addition of whole numbers. 2018-04-30 Brad pose la question :I found this on your site. Question: what is the sum of the first 100 whole numbers?? Is there a different formula if the numbers begin at a number other than one? For example What is the series I want to add is goes from 7 - 53?Harley Weston lui répond. Adding two negatives 2018-02-04 Pinasshakoane pose la question :(-23)+(-3)Penny Nom lui répond. Multiplication and repeated addition 2016-11-23 Anandmay pose la question :Hello I was looking closely at early arithmetic where I found how we discovered properties of Arithmetic. Like:2 x 3 = 3 x 2. This can be proved by considering a 2-D figure(actually,quadrilateral) having length consisting of 2 boxes of 1-by-1 dimensions and breadth of 3 boxes of the same dimensions. Now,consider it again,but,this time,length of 3,and breadth of 2 of such 1 by 1 boxes. We now notice that we can fit the 2 types of rectangles formed on each other precisely. So the multiplicative property of commutativity is true for all natural numbers as we can generalize the result(in our mind,for self satisfaction). Now,can you find me a nice satisfactory reason of why a fraction times a natural number equals the number times the fraction? I mean, for example,i can understand the meaning of 3 x 2/3 to be three times 2-3rd,that is, 2/3+2/3+2/3.Fair enough. But here is the problem:By definition and actual meaning of multiplication, a x b means the repeated sum of b,done 'a' times. So what is the meaning of doing 2/3 x 3?The repeated addition of 3 how many times??2/3 times??Not making sense,right?And even we have not proved yet the commutative property of numbers INCLUDING fractions.So how can we resolve this problem and make these things meaningful? ThanksPenny Nom lui répond. Complex numbers in standard form 2016-01-15 Michael pose la question :express the following complex numbers in standard form (2+3i)+(5-2i)Penny Nom lui répond. Multiplication and order 2011-01-21 Janet pose la question :IN A MULTIPLICATION SENTENCE BASED ON A DRAWING..IS THERE ANY ORDER FOR THE MULTIPLICAND ANG MULTIPLIER FOR THE ANSWER TO RIGHT?Robert Dawson lui répond. Convert to multiplication 2010-10-23 angelina pose la question :how to covert 5+5+5=15 to multiplicationPenny Nom lui répond. 4.5 PLUS 29 2010-09-07 kiona pose la question :4.5 PLUS 29Penny Nom lui répond. Adding in base six 2009-03-29 Lucy pose la question :If you are working in base 6, what do you have to add to 4(base 6) to get 10(base 6)????Penny Nom lui répond. Adding fractions 2008-09-17 amanpreet pose la question :please can you help me to simplify: 2(c-3) / 7 + 3(4c-2)/2Penny Nom lui répond. .9 repeating plus .2 repeating 2008-06-10 megan pose la question :How do you express the addition of .9 repeating plus .2 repeating?Penny Nom lui répond. Adding rational functions 2008-04-29 Jonathon pose la question :1/(x+3) + 1/(x^2+5x+6) =Penny Nom lui répond. Base 5 arithmetic 2008-03-06 Jana pose la question :Hello, my name is Jana, i have asked a question here previously about how to count in base-5. I am happy now because i can convert any number now and it is very easy for me. The only thing i am having trouble with is understanding how to do a maths sum or times base-5 numbers. it is just a bit hard for me. So do you think you could explain how to do a sum in base-5 and how to do a multiplication sum. Please help...Thankyou Jana!!Harley Weston lui répond. Adding fractions 2007-12-31 Lisa pose la question :As an educator in Adult Education, I am preparing a young man for a US Government test. The equation I have trouble with is explaining the following equation. It asks: If it takes A 3 days to dig a certain ditch, whereas b can dig it in 6 days, and C in 12, how long would it take all three to do the job? I know the equation is 1/3 + 1/6 + 1/12 and it equals = 7/12 but I don't understand how it equals 7/12. This simple math eludes me. So the question is not the final answer of 1 and 5/7 of days but where one comes up with the 7/12?Penny Nom and Claude Tardif lui répond. Linear systems 2006-09-21 Alexander pose la question :Hello, i have a math assignment due tonight at midnight and i need some help please It is using the addition method to solve linear systemsPenny lui répond. 1/x + 1/y 2006-08-11 Sonya pose la question :what is 1/x+1/y = ? is it equal to 1/x+y or what?Penny Nom lui répond. Adding polynomials and counting the terms 2006-04-28 Kris pose la question :Suppose that two polynomials, each containing 3 terms, are added. Is it possible for the sum to contain more than 3 terms? fewer than 3 terms? exactly 3 terms? Explain.Leeanne Boehm and Steve La Rocque lui répond. Adding 10 and multiples of tens to one and two digit numbers 2005-12-13 Meghan pose la question :I am teaching in a grade 2/3 class and I am struggling with trying to find a simple way of explaining to the students how to add 10 and multiples of tens to one and two digit numbers.Diane Hanson lui répond. Adding fractions 2003-11-16 Ken pose la question :My name is Ken and I am taking my GED course for my High School and have not been in a class for 35 years. I am doing this for re-training. I am at the part about fractions. Here is an example that I am having trouble with. 1 3/7 + 4 2/3 + 11/21 They have no common denominators. Could you PLEASE help me. If you could send me a step by step explanation it would be greatly appreciated.Penny Nom lui répond. Common Denominator 2002-08-26 Slobodanka pose la question :What is a Common Denominator?Penny Nom lui répond. Adding algebraic fractions 2002-03-20 Dolores pose la question :I get totally confused with this problem. I get confused with the getting the lowest terms. 4/x-5 + -2/x -10/x^2-5x Penny Nom lui répond. F = -3 + 3 2002-03-19 Jessica pose la question :F= -3 + 3 WHAT IS F?????Penny Nom lui répond. Adding algebraic fractions 2002-01-23 Francine pose la question : Hello, I've come up with an answer for the following problem but it's not the same as the book's answer. However, the book has a lot of mistakes in it and I don't know if I'm doing it properly or not. Your help would be soooo appreciated. It's driving me crazy.The problem is: ``` 2 + 3 + 4 --------- + --------- + ---------- (x-1)^3 (x-1)^2 (x-1) ``` [(x-1)^3 is (x-1) to power of 3 etc.] Penny Nom lui répond. Adding vectors 2002-01-12 Lena pose la question :how do you add vectors together? If you are given the length and angles of both vectors and are asked to add/subtract them, how do you do it? I know you are supposed to do the head to tail method, but whenever i try it i get the wrong answer. I need help setting it up. example: A is 2.7cm, and 60 degrees, B is 1.6cm and 135 degrees, find the magnitude and amplitude Penny Nom lui répond. Odd plus even is odd 2001-10-14 James pose la question :Why is the sum of an odd number and an even number always odd?Peny Nom lui répond. Adding functions 2001-02-19 Jackie pose la question :f(x) = x2 + 1; g(x) = x2 - 1 find a) ((f+g) of h)) (x) b) ((f-g) of h)) (x) c) ((f of h) - (g of h)) (x) Penny Nom lui répond. What is wrong with these probelms? 2001-02-09 Cindy pose la question :Hi, I am a planning on becomming a teacher and i am asked to find out what is wrong with these probelms and how i would go about showing a student what is wrong with them!! Error in patterns: 13/35=1/5; 27/73=2/3; 16/64=1/4 4/5+2/3=6/8; 2/5+3/4=5/9; 7/8+1/3=8/11 2/3*3=6/9; 1/4*6=6/24; 4/5*2=8/10 Leeanne Boehm and Penny Nom lui répond. Order of operations 2000-11-26 Margaret Pratt pose la question :My daughter has a math question and I am afraid I am of no help. Can you help? 2x5/2+1-5= She arrives at 8 as the answer and has been told this is incorrect. Any help you can give would be appreciated.Penny Nom lui répond. Word addition 2000-07-05 Harman Chaudhry pose la question :What is the value of DISHES if SEE + THE + WAITER + WASHES = DISHES. In addition, I know there is a name for these types of problems--what are they actually called?Chris Fisher lui répond. Why does division start from the left? 2000-05-24 Salil Dave pose la question :Addition, subtraction and multiplications start with right most digit and proceed left, but division starts from left-most digits and goes right ... why? Harley Weston lui répond. Adding fractions 2000-04-23 A grade 6 student pose la question :In adding fractions, how do I rewrite the fractions so that the denominators are equal? The problem is 3/4 + 1/6 = The other problem is 11/18 + 4/9 =Penny Nom lui répond. Addition 2000-01-11 Deanna pose la question :what is the answer for 20+5+32-3+98Penny Nom lui répond. A number between 1998-11-25 Jimmy Nikola pose la question :A number is less than 3,425 + 8,630 and greater than 7,614 + 4,429. What could the number be? This question is on page 93, question number 23. in Silver Burdett Ginn Math book, which is a 3rd grade math book.Jack LeSage lui répond. Adding Fractions 1998-10-15 Lindsay pose la question :please help me!!!!Harley Weston lui répond. A Sum or Product of Fractions 1998-10-06 Emily Robb pose la question :Find a pair of fractions that when they are multiplyed and added the sum /product is the samePenny Nom lui répond.