Explanation:
Hi,
For the first one...
Input: 0 Output: 1
Input: 2 Output: 2
Input: -8 Output: -3
Input: 100 Output: 51
And then for the creat your own...
Divide by 5 and add 3
Input: 50 Output: 13
Input: 25 Output: 8
Input: -75 Output: -12
Input: 150 Output: 33
I hope this helps :)