Answer:
It's very simple. In 4 decimal digits there are 10,000 (0000 to 9999) possible values. The odds of any one of them coming up randomly is one in 10,000. A specific "4 digit number" would have 1/9000 chance, since there are 9000 4 digit numbers (1000-9999).
Step-by-step explanation:
let x =the number
Step-by-step explanation:
81+x=3x-39
group like terms
81+39=3x-x
120=2x
120/2=2x/2
60=x
therefore x =60
Switch y and x to find the inverse:
x = 3y - 8
Now just solve for y
y = x/3 + 8/3
