Subject: General Aptitude · Chapter: Number System · Exam: 2006 · Marks: · Difficulty:
On multiplying a number by 7, all the digits in the product appear as 3's. The smallest such number is
(a)47619
(b)46719
(c)48619
(d)47649
Answer
Answer (as printed): A
Explanation
We keep on dividing 33333... by 7 till we get 0 as remainder. $$\begin{gathered} 47619 \\ 7) 333333( \\ \frac{28}{53} \\ \frac{49}{43} \\ \frac{42}{13} \\ \frac{7}{63} \\ \frac{63}{\times} \\ \hline \end{gathered}$$ ∴ Required number $=47619$
Explanation as extracted from the printed page; notation may be imperfect.