# find the odd one out of the following options 15,21,63,81

Dear Student,

We have :  15 , 21 , 63 , 81

All are odd numbers .

And

15 =  3 $×$ 5

21 = 3 $×$ 7

63 =  3 $×$ 21

81 = 3 $×$ 27

All are multiple of " 3 " .

Here we can't find odd number from given numbers : 15 , 21 , 63 , 81

So,