Question

Which of the following pair of numbers is not divisible by $9.$

• A. $225,631$
• B. $532,304$
• C. $243,234$
• D. $711,585$

Answer 1

The correct option is B $532,304$

The number, whose sum of digits is a multiple of $9,$ is divisible by $9.$

Let's add the digits of the numbers of each pair.

$225,631$
$225\to 2+2+5=9$
$631\to 6+3+1=9$
$\therefore$ These pair of numbers are divisible by $9.$

$531,304$
$531\to 5+3+2=10$
$304\to 3+0+4=7$
$\therefore$ These pair of numbers are not divisible by $9.$

Similarly, $\{243,234\}$ and $\{711,585\}$ are divisible by $9.$

$\therefore$ The correct option is $b.$