Question

The given pair of numbers $231,396$ are __________ .

• A. multiple of each other
• B. factors of each other
• C. co-prime to each other
• D. having a difference of $120$ among each other

Answer 1

Answer: (C)

co-prime to each other

Euclid's division lemma,

$a=bq+r$ ; $0\le r<b$

Applying Euclid's Algorithim to $231,395$

$395=231\times 1+164$

$231=164\times 1+67$

$164=67\times 2+30$

$67=30\times 2+7$

$30=7\times 4+2$

$7=2\times 3+1$

$2=1\times 2+0$

The given numbers have only $1$ as common factor.

Hence, the given numbers are co-prime.