It's not time to try and simplify it until you HAVE an equation. You won't have an equation until you write down what. V*4x is equal to.
well, we know that 213.90 includes the 15% gratuity, so if the meal price was say "x", namely that is the 100%, and we add 15% to that, then 100% + 15% = 115%, so 213.90 is really the 115%.
now, if 213.90 is the 115.%, what is "x"? the 100%.

so since we know the meal without the tip is 186 bucks, the tip was then 213.90 - 186 = 27.90.
but they got extra potato wedges with butter and the waitress was wearing her best hat, they added $20 more, so the tip ended up as 27.90 + 20 = 47.90.
now, if the cost of the meal was $186 and that is the 100%, what is 47.90 off of it in percentage?

Answer:
16
Step-by-step explanation:
This question can be modeled using the equation 3x+4=52 (x is the purple marbles). To solve this equation subtract 4 from both sides, making it 3x=48. divide both by three showing x=16. This shows that 16 is the answer.
Answer:
r = √98
Step-by-step explanation:
angle A and the diameter form an isosceles right triangle, with OA as the hypotenuse and r as the other sides. You can then make and solve an equation from the Pythagorean Theorem:
r^2 + r^2 = 14^2
2r^2 = 14^2
2r^2 = 196
r^2 = 98
r = √98