Ask Questions, Get Answers

Want to ask us a question? Click here
Browse Questions
Home  >>  CBSE XI  >>  Math  >>  Permutations and Combinations
0 votes

A seven-digit number made up of all distinct digits 8,7,6,4,2,x and y is divisible by 3.Then possible number of order pair (x,y) is

$\begin{array}{1 1}(A)\;4\\(B)\;8\\(C)\;2\\(D)\;\text{None of these}\end{array} $

Can you answer this question?

1 Answer

0 votes
$8,7,6,4,2,x$ and $y$
Any number is divisible by 3,if sum of digits is divisible by 3
(i.e) $x+y+27$ is divisible by 3
$x$ and $y$ can take values from 0,1,3,5,9
Possible pairs (5,1),(3,0),(9,0),(9,3) and (1,5),(0,3),(0,9),(3,9)
Hence (B) is the correct answer.
answered May 19, 2014 by sreemathi.v

Related questions

Ask Question
student study plans
JEE MAIN, CBSE, AIPMT Mobile and Tablet App
The ultimate mobile app to help you crack your examinations
Get the Android App