Question

A new phone costs $230 and the sales tax rate is 7%. What is the total cost of the camera after tax?

Answer 1

That's a question about percentage.

One way to represent percentage is using decimal number. In this way, 1 is equivalent to 100% and the other less percentages using numbers between 0 and 1.

Examples:

• 90% is equivalent to 0,90.
• 5% is equivalent to 0.05. It's not 0.5 because 0.5 is equivalent to 50%.
• 13.17% is equivalent to 0.1317.
• 245% is equivalent to 2.45.

If we want to know the percentage of a number, we should multiplacate the number by the porcentage in the decimal number form.

Examples:

• 55.90% of 200 is equal to:
  `200 * 0.5590 = 111.8`

• 360% of 88 is equal to:
  `88* 3.6 = 316.8`

In our problem, we have a phone with a increase of 7%. To solve that, it's important to perceive that $230 is equal to 100% and with a increase of 7%, we will pay 107%.

107% in the decimal number form is 1.07. With that information, we should multiplicate 1.07 by the original value and we will find the answer.

We know that
`230* 1.07 = 246.1`, therefore, the total cost of the phone after tax is $246.1.

I hope I've helped. :D

Enjoy your studies. \o/