Question

abc is a three digit number such that sum of its digits is 3.
abc + bca + cab = ?

• A. 111
• B. 333
• C. 222
• D. 555

Answer 1

The correct option is B 333

Here, $abc=100a+10b+c$
$bca=100b+10c+a$
$cab=100c+10a+b$

$abc+bca+cab$
$(100a+10b+c)+(100b+10c+a)+(100c+10a+b)$
$=100a+10a+a+100b+10b+b+100c+10c+c$
$=111a+111b+111c$
$=111(a+b+c)$
$=111\times 3$ (Since a + b + c = 3)
= 333​​