I hope this makes sense, if not please feel free to let me know and I'll explain it.
Because if you multiply 2 different irrational numbers (like the following)

You will get an irrational answer.
BUT
if you multiply the same square root (which are both irrational, you get a rational number)
We can represent the cost of the notebooks with by saying 0.75n, and the cost of the pens by saying 0.55p.
0.75n+0.55p will be the total cost before tax. Now, we need to add on tax. Tax will be 0.0625 times the total amount, so we can represent the cost by saying
(0.75n+0.55p) + 0.0625(0.75n+0.55p), so the answer is B.
Answer:
try making a porportion with 57 and 51
Step-by-step explanation: