  Math Central - mathcentral.uregina.ca  Quandaries & Queries    Q & Q    Topic: divisibility by 9   start over

8 items are filed under this topic.    Page1/1            4821x14y is an 8-digit number divisible by 72 2014-08-06 From RAYA:if 4821x14y is an 8-digit number divisible by 72. How many values can x and y take?Answered by Penny Nom.     A 4 digit number 2014-04-04 From LIM:"A" is a 4 digit number formed by all the numbers from 1 to 4. When "A" is divided by 9, the remainder is the biggest possible value. What is the biggest value of A?Answered by Chris Fisher.     An even multiple of 27 2011-02-01 From parth:the 6 digit # 63x904 is an even multiple of 27 what is XAnswered by Penny Nom.     Powers 2010-10-20 From dylan:how do you write 20736 in exponential form .same for 1728 and 50625. is there a formula to figure out how to express large know numbers in exponential form.Answered by Penny Nom.     Divisibility rules 2001-09-07 From A student:Why is it that when you add the digits of a number you can tell what the multiples of that number are. Example: 12131313111, 1+2+1+2+1+3+1+1+1=18, therefore 12131313111 is divisble by 2, 9, 18, & 3 because those numbers are divisble by 18. Answered by Penny Nom.     Divisibility by 9 2000-10-24 From Kelera:If the sum of the digits of a number is divisible by 9, then the number itself it divisible by 9. Why is that? How do you explain this? Answered by Penny Nom.     Divisibility by 3 2000-03-24 From Pat Walsh:W hy does it work when you add the digits of a number then divid by three to see if the number is divisible by threeAnswered by Penny Nom.     Divisibility by 9 1999-02-21 From Razzi:I've been having a hard time trying to solve the following problem and I was wondering if you could help me. For any positive integer a let S(a) be the sum of its digits. Prove that a is divisible by 9 if and only if there exist a positive integer b such that S(a)=S(b)=S(a+b). Answered by Chris Fisher and Harley Weston.      Page1/1    Math Central is supported by the University of Regina and The Pacific Institute for the Mathematical Sciences.    about math central :: site map :: links :: notre site français