Solution
: Let the first even number $=x$
Then, second even number $=x+2$
and third even number $=x+2+2=x+4$
According to question, $x+x+2+x+4=42$
or, $3 x+6=42$
or, $3 x=42-6=36$
or,
$x=\frac{36}{3}=12$
First even number $=12$
Second even number $=12+2=14$
Third even number $=12+4=16$