Question

Find the values of the letters in the following and give reasons for the steps involved.
$1A\underset{–}{\times A}\underset{–}{9A}$

Answer 1

According to the question that when a digit $A$ multiplies with itself then the unit digit of the answer should be $A$.

$1,5$ and $6$ are those numbers which satisfy the above condition

so put $1,5$ and $6$ in place of $A$ and check

$11\times 1=11$

$15\times 5=75$

$16\times 6=96$

So, the value of $A$ is $6$.