Squares ending with 5 - Interesting Number Pattern ---> 21

Notice this pattern for squares ending with 5

05 * 05 = 0025 ---> 00 + 25 = 25 ----> Subtract the original number 5  = 25 - 5 = 20
15 * 15 = 0225 ---> 02 + 25 = 27 ----> 27 - 15 = 12
25 * 25 = 625  ----> 06 + 25 = 31 ----> 31 - 25 = 6
35 * 35 = 1225 ----> 12 + 25 = 37 -----> 37 - 35 = 2

The sequence starts froom 20 and comes down to 2. Now notice this

45 * 45 = 2025 -----> 20 + 25 = 45 ------> 45 - 45 = 0
55 * 55 = 3025 -----> 30 + 25 = 55 ------> 55 - 55 = 0

So two zeroes in between as the difference... Now...

65 * 65 = 4225 -----> 42 + 25 = 67 ------> 67 - 65 = 2
75 * 75 = 5625 -----> 56 + 25 = 81 ------> 81 - 75 = 6
85 * 85 = 7225 -----> 72 + 25 = 97 ------> 97 - 85 = 12
95 * 95 = 9025 -----> 90 + 25 = 115 -----> 115 = 95 = 20

It shows the increasing pattern from 2 to 20 :)

Completes a full circle!