$4
You can get this by setting up 2 equations. One for you and one for your friend. Each should have a cost equation. Let x = adult and y = student.
You: 7x + 16y = 120
Friend: 13x + 9 = 140
Solve using any method.
3/15 means if you pay the bill within 15 you will get a discount by 3%
Now solve your question
178.95−(178.95×0.03)
=173.58 be paid
Answer: C) 9/41
Step-by-step explanation: The ratio for cosine is adjacent/hypotenuse. 9 is the adjacent side and 41 is the hypotenuse.