Quiz 2
Aubrey's dinner cost $85. She tips the waitstaff 30% for excellent service.
How much does Aubrey tip the waitstaff?

The answer I got was $25.5.

Step-by-step explanation:

I first did 30/100 since 30 is a percentage.

Next I put x/85 since 85 is the total cost.

Now I have 100x=2550

I crossed off one zero from both of the numbers because it’s dividing.

Now I’m stuck with 10x=255.

After dividing, I got 25.5.

or

step-by-step explanation:

we need to solve for 'x' the following equation:  

we have that:

⇒

⇒ ⇒

factorizing, we get that:

  ⇒

then, the solutions are: or

nothing extraneous has been found!