Answer:
The required number is -15.
Explanation:
Given : Expression 'Fifteen decreased by the quotient of a number and 3 is 20'.
To find : The number ?
Solution :
Let the number be 'x'.
According to statement,
Fifteen decreased by the quotient of a number and 3 is 20,

Solving the equation by subtracting 15 both side,

Cross multiply,


Therefore, The required number is -15.