Question

how to find patterns in the multiples of 5

Answer 1

a number that is a multiple of 5 will either end in 5 or 0.

5
10
15
20
25
30
35
40
45
50
etc...

notice they all alternate between 5 or 0.

if a number does not have this condition, it isn't a multiple of 5

Answer 2

05
10
15
20
25
30
35
40
45
50
etc...


Notice that digit on right changes continuously from 0 to 5 and 5 to again 0.

And the digit on left is changing after two values like 1,1 then 2,2 then 3,3 likewise..(except 0).