Question

how to find out reverse a number

Answer 1

if  986 is a number, then its value is  9 * 100 + 8 * 10 + 6
Then its reverse is  , 689,  ie.,  6 * 100 + 8 * 10 + 9

so if abcd is a number, then its reverse is :
   there are 4 digits.

$a*10^{(4-1)}+b*10^{4-2}+c*10^{4-3}+d=a*1,000+b*100+c*10+d\\Reverse\ is:\\\\d*10^{(4-1)}+c*10^{4-2}+b*10^{4-3}+a\\1000*d+100*c+10*b+a$

Answer 2

If  446 is a number, then its value is  4 * 100 + 4 * 10 + 6
Then its reverse is  , 644,  ie.,  6 * 100 + 4 * 10 + 4

So if ABCD is a number, then its reverse will also a four digit number .