Question

a, b, c (a > c) are the three digits, from left to right of a three digit number. If the number with these digits reversed is subtracted from the original number, the resulting number has the digit 4 in its unit's place. The other two digits from left to right are -

• A. $5and4$
• B. $5and9$
• C. $4and5$
• D. $9and5$

Answer 1

The correct option is B $5and9$

Given that, a > c. Hence $10+c-a=4$ (subtraction at unit's place)
Middle digit is reduced by 1, hence $10+(b-1)-b=9$ (subtraction at ten's place)
Hundred's digits now give (a-1-c) (subtraction at hundred's place)
From $10+c-a=4$, we get $a-c=6$
$\therefore a-c-1=5$