Question

Find the values of the letters in the following and give reasons for the steps involved.
$2AB\underset{–}{+AB1}\underset{–}{B18}$

Answer 1

If $B+1=8$, then $B$ has to be $7$.

Now we have

$A+7$ has to end with $1$, so it has to be $11$,

$\therefore A$ has to be $4$.

Then, $2+A+1($carry over$)=B$

Thus, $A=4,B=7$