Javier and his friends go out to eat. the restaurant they chose automatically adds a 15% gratuity to their food bill since they are a party of 12. the total bill after the automatic 15% gratuity was $213.90. because they received such good service, the group decided to add an extra $20 to the total bill as an additional tip. so, instead of leaving a 15% tip, javier and his friends ended up leaving a tip that was about% of the food bill

The Tip was 25.75% of the food bill

Step-by-step explanation:

Hello, great question. These types are questions are the beginning steps for learning more advanced Algebraic Equations.

Before we can calculate the percent of the total tip we need to calculate the original food bill before the 15% gratuity fee. We need to create a formula in order to solve this. Since the food bill plus the gratuity fee equals $213.90 then we can say ....

.... combine like terms

.... divide both sides by 1.15

Now we can see that the food bill is $186. Now we can calculate the amount of the tip and add the $20 that the group added by subtracting the original total by the food bill.

Finally, to find the percent of the food bill that was left in tips we divide the tip total by the food bill.

The Tip was 25.75% of the food bill

I hope this answered your question. If you have any more questions feel free to ask away at .

i think it would be 42cm

{x = -1/2 ,   y = -1

step-by-step explanation:

solve the following system:

{2 x + y = -2

{10 x - 3 y = -2

in the first equation, look to solve for y:

{2 x + y = -2

{10 x - 3 y = -2

subtract 2 x from both sides:

{y = -2 x - 2

{10 x - 3 y = -2

substitute y = -2 x - 2 into the second equation:

{y = -2 x - 2

{10 x - 3 (-2 x - 2) = -2

10 x - 3 (-2 x - 2) = (6 x + 6) + 10 x = 16 x + 6:

{y = -2 x - 2

{16 x + 6 = -2

in the second equation, look to solve for x:

{y = -2 x - 2

{16 x + 6 = -2

subtract 6 from both sides:

{y = -2 x - 2

{16 x = -8

divide both sides by 16:

{y = -2 x - 2

{x = -1/2

substitute x = -1/2 into the first equation:

{y = -1

{x = -1/2

collect results in alphabetical order:

answer:   {x = -1/2 ,   y = -1