In order to calculate the value of this expression, we first need to calculate the products and divisions, then we calculate the subtraction.
First, calculating 5 times 5, we have 25.
Then, the division of 4 and 5 is equal to 0.8.
Finally, calculating the subtraction of 25 and 0.8, we have 24.2.
Therefore the result of this expression is equal to 24.2.