Respuesta :

Answer

$9

Solution

20%:$1.80
1%:$0.09
100%:$9.00

Answer:

$9 before tip

Step-by-step explanation:

Let's find the price of Mira's breakfast.

Ususally a tip is calculated by a defined percentage, and it means that from the actual price of the breakfast you add to the bill a X% of the price.

This means that if your breakfast price is Y, the tip (T), using a X percentage for tip, can be calculated as:

T=Y*(X/100); notice how 'tip percentage' (X) is divided by 100 to convert a percentage number into a decimal number.

In the given problem, Mira uses a 20% 'percentage tip' which means X=20. Also, Mira leaves a $1.80 'tip' which means T=$1.8.

Now, the problem asks the price of the breakfast (Y), so using the previous equation, we have:

T=Y*(X/100)

$1.80=Y*(20/100)

$1.80*100/20=Y

$9=Y

In conclusion, the price of Mira's breakfast is $9 before tip.