Answer:
7f
Step-by-step explanation:
To simplify you will need to do it the same way as in adding natural numbers the variable doesn't change the number
So it's going to be;
9f+10f-12f
(Nine plus Ten is equal to 19)
•The variable remains the same
19f-12f
•So you subtract 12 from 19 which is going to be;
7f
