Please help with this Math Level 2 question!?

The postal rate for first-class mail is 44 cents for the first ounce or portion thereof and 17 cents for each additional ounce or portion thereof up to 3.5 ounces. The cost of a 3.5-ounce letter is 95 cents. A formula for the cost in cents of first-class postage for a letter weighing N ounces (N ≤ 3.5) is
A) 44 + [N-1] * 17
B) [N-44] * 17
C) 44 + [N] * 17
D) 1+ [N] * 17
E) none
The answer is E. Also, keep in mind that [x] is the greatest integer function. I just want to know what the equation would actually be if it isn’t any of the above.
Thanks!

There is no general equation. Each case has its own equation, because it is impossible to combine both cases.

This questionis from PR, right? I remember I chose A, that´s why I failed Math L2

There is obviously a missing variable in this question needed to get a correct equation. The part you have to focus on is that 3.5oz=$.95. Since none of those equations at N=3.5 equal 95, the answer must be E.

Yes, there is obviously a discontinuity because at N=3.5 it jumps to a different value. I would just plug in N=3.5 to make sure next time.