Question

If a $6$ digit number $abcdef$, when multiplied with $6$ gives the resulting number as $defabc$, then the value of $a+b+c+d+e+f$ is

• A. $28$
• B. $27$
• C. $26$
• D. $24$

Answer 1

The correct option is B $27$

If 6-digit number $abcdef$ is multiplied with $6$ and the resulting number is $defabc$

Then, $6\left(abcdef\right)=defabc,6(1000abc+def)=1000def+abc$

$5999abc=994def$

$\Rightarrow 857abc=142def$ ,

$\Rightarrow abc=142,def=857,$

Therefore, the number is $142857.$

Hence, sum $=27.$
Hence, option B.