Question

Find out (A + B + C + D) such that AB x CD = DDD where AB and CD are two-digit numbers and DDD is a three-digit number

• A. 21
• B. 13
• C. 17
• D. 19

Answer 1

The correct option is B 13

$AB\times CD=DDD$
Hence DDD has a factor of D and 111 and 111 has factor 3 and 37
$DDD=(3\times 37\times D)=AB\times CD$
Thus either AB or CD is 37 and other number is $D\times 3$
If D=5 then
$37\times (3\times 5)=555$
$37\times 15=555$
Hence $A=3,B=7,C=1,D=5$
$A+B+C+D=16$
if D=7
$37\times (3\times 7)=777$
$21\times 37=777$
Hence$A=2,B=1,C=3,D=7$
$A+B+C+D=13$