Answer:
The original number is 82
Explanation:
Very interesting question!
There is only 1 number that satisfies this condition between 10 and 9999 (I could have gone much further but didn't)
That number is 82
If you subtract 7 from 82 you get 75
75/5 = 15
If you subtract 5 from 82 you get 77
77 divide by 7 = 11
Here's the kicker.
11 is 4 less than 15.
Isn't that a weird coincidence? No other number (I would bet) does that.